Knowledge and Limitations

00:00:00 so I will introduce the uh participants today I will not go through everything here because I think all of you have already uh so just a summary of things uh pranada nataran is a professor of astronomy and physics at yel University and her research is focused on Exotica in the universe Dark Matter dark energy and black holes she is obviously very very prominent in her

00:00:31 field and also holds professorships at the Tio Bria Sophie and Tio Bri professorship uh at the ne at the NS board Institute in Copenhagen Denmark and honorary professorship at the University of Delhi in India uh Tim mlin uh oh Peri has been here before with us and so has Tim Tim is a professor of philosophy at New York

00:01:02 University and uh his most recent book recent books are philosophy of physics space and time and New Foundations for physical geometry DTI vuk I think is her first time here she's professor of Germanic languages at Colombia University and uh she is just she has a number of books that are listed here her latest book which I guess is not out yet is is uh on uh changing models of

00:01:33 authorship and creativity in the Arts and Sciences during the long 18th century so with that I'll uh let you start there's no okay I I thought we were going to be posed question no questions you've got a whole list of I have a whole list of things here to get so I guess I was curious um about trying

00:02:04 to understand whether the way the the theme was posed to us I read it as whether there are fundamental limits that may prevent extension of knowledge in um Beyond certain points and so from the vantage point of cosmology so there sort of obvious limitations first in the sense that there's a limit to observation in the sense because the

00:02:34 speed of light is finite there's only a portion of the universe that is observable to us at any given time so given the finite age of the universe and finite speed of light there is what is called an observable Horizon so you are not privy to what is happening Beyond you have no knowledge of what's Happening beyond that current Horizon of course that Horizon shifts as time goes on so billion years later more

00:03:04 of the universe will come into view but at any given point there's sort of a hard boundary of where you cannot get any information from and of course you know in quantum mechanics we also know that you know Heisenberg's uncertainty principle tells you that you cannot simultaneously know the position and momentum of um of an object simultaneously so so there's like you know one can sort of view that sort

00:03:36 of as a limit so when there's a limit to sort of observation then there's a limit because I mean I'm thinking about Cosmos um and Cosmic scales there's also limit to travel right so question of interstellar interpace travel and that of course again has to do with you know it's not just a technological limitation it has to do with the human lifespan the fact is even if we the technology that could Propel us outside

00:04:07 the solar system and take us to planets around other stars and so on so forth the fundamental limitation is there is a finite human lifespan and we can't circumvent that even if we come up uh with ways to fuel rockets that can fly for 10,000 years or whatever powered right so um so I sort of thinking about that and then saying there is a limit ation also to human lifespan no that human lifespan being what it is will contain will necessarily gives you a

00:04:39 limit on travel I understand that but are you're saying there's no way to extend human lifespan Beyond a certain point there may be I'm um not sure if it will be enough to take us to planets around other stars because you know the point is now we're finding all these soal called habitable planets around other stars the question you know at least for someone like me the first question is is there any means by which we will actually reach it and then you realize that there's a fundamental limitation

00:05:10 you wouldn't um then if you look at sort of limits to the there are limits to the kinds of um energies at which you could build colliders like at CERN the LC you know you can go up by factor of 10 factor of 100 and so on so there's sort of a fundamental limit in terms of the time that it is going to take to build something like that like how many generations would it span um of course as well as cost and

00:05:42 other sort of practical things but once again you know sort of the human lifespan comes into view when you look at trying to understand the constituents of the cosmos so you I was really looking from that point of view trying to understand our place in the universe and um stuff like that and then the question the one U point that I think is very interesting is sort of the limit limits on thought so and I think that's where one

00:06:14 of the reasons you know everyone's teasing me about my notes is that you know trying to stay to stay focused and stable in my own opinion there's a bit of me that feels that there is no reason to believe that human cognitive capacity should be infinite that there have there are billions of millions of nerve cells but um the fact they're not infinite and although the brain is plastic and it

00:06:45 does Morphin it does learn even as we age and now we know that it's not clear to me that it responds fast enough given you know what remains to be understood so so that's like a fundamental limit that comes from just complexity she complexity of whether we have the cognitive apparatus to Fathom understand all the complexity and I think um I'm not sure that we do um I I mean I see no reason

00:07:15 to believe why we do um should I yeah let me let me just jump in and and respond uh or say some things maybe in the in the general area um I mean I have two oh great yeah I have two backgrounds one in in philosophy and one more in in physics of course if you're a philosopher uh you're going to say the limit of to human knowledge is that we

00:07:46 have pretty much none of it about anything uh that is all of our beliefs are tenative to some degree you could say we have tremendous amounts of evidence for things but we know sometimes well- entrenched beliefs get overthrown later so part of it is just to say we should always be very tentative to some degree or or a little bit humble about anything we think we know so it's more a question of limits on evidence limits on reasons to believe um and then the second thing I suppose

00:08:18 when you talk about limits it sounds like gee that's a terrible thing um but you but you you ought to stop and ask for a second what you really care about because there may be things which we we we won know um but on further reflection we don't care all that much about um I could pick out a tree in Central Park and say nobody knows how many leaves there are and I guess in principle you could go count them but nobody's going to right you know by next spring nobody will ever know it's kind of a piece of trivia um so there's a whole lot of trivia about

00:08:49 the universe but and we shouldn't be too upset um then there are more fundamental issues we'd really like to have settled and uh the limits there are very interesting I'll just mention one thing um to to to to to show you how tricky it is in physics pre the Heisenberg uncertainty relation which probably most people have heard of one way or another uh and described it this way that you can't simultaneously know say the position and momentum of a of a particle

00:09:20 which you also might think is kind of a bit of trivia but the even the way that's phrased is contentious um the way it's phrased it suggests that a particle always has a definite position in momentum and we just can't know them both at the same time um but some understandings of quantum theory say no that's not the way right way to think about it the right way to think about it is that particles just don't have them both at the same time so there's nothing we're ignorant

00:09:51 of um now that's going to differ on different understandings of the theory and then that leads us to the question can we settle that dispute can we decide between different fundamental physical pictures of the universe and the interesting thing there is that I think Einstein pointed this out how much you can find out about the physical world is itself a function of what the physical laws are you sort of have to ask the the how much you can

00:10:21 know about the world because we only acquire information by physical interaction with the world so the physics self can put limits on what an Inquirer can find out about the physics or the physics itself could as it were make put us in a position where we can't know what the be sure what the physics is so I I think those are very interesting because I actually just personally care about knowing the fundamental laws of nature more than the leaves on the trees um that's the kind of thing that that worries me a bit

00:10:54 um how do you react to that well if that's the way the world is you live with it I there's lots of things about the world you wish could be different um and I think we'll we'll only know when we when we have you know we'll continue this why is it you wish to know more I would like to know what the fundamental laws of nature are why that's an interest I mean that's just part of my intellectual character I mean I was bouncing around doing phy why philosophy because somehow you get down to the bottom of everything right and then

00:11:26 doing some science and you say oh biology that's interesting but really it's just chemistry you know chemistry that's interesting but really it's just physics okay what's really physics now um lots of people could feel differently they could feel I I I just really enjoy studying cells and I couldn't care less about electrons um but the that same kind of desire to somehow in a certain sense get to the very bottom is just that's why I'm interested here so but but you don't mean that anything would change if you knew that you mean that you just are

00:11:56 interested in it I it it nothing would I have a desire to know the facts th those particular facts and I would be pleased if I could find them out um the rest of my life would go on as usual make breakfast the same way you know my my interactions with people would be the same my political views wouldn't change you could say all of this is a little bit you know isolated from lots of other big questions in life um but it it's something that just

00:12:27 fascinates me yeah I'm probably the fth on the laws of nature in the universe since I'm in Lent intellectual history but when I thought about the topic we're discussing um I couldn't help but think well the limitations are not just negative as upra brought up the issue of increasing complexity whenever you study something uh there

00:12:58 you'll reach a a point where you need to reduce the complexity and um you bring up the question of the limited lifespan human being and um in a way the opacity of the observation process so I thought it's probably productive also to think about these limitations in terms of the situatedness of any situation of knowledge production knowledge communication it's language on

00:13:31 institutions um that have their power and whenever we declare something to be an important research program that deserves funding or that should be taught rather than something else their interests that have their own um institutional Dynamics and political ramifications so um and then there are culturally historically

00:14:02 changing um conventions of what constitutes objectivity what constitutes facts what con constitutes evidence and um I I I was going to propose to think about the limitations of knowledge in terms of situatedness of the production of knowledge which I guess cannot be

00:14:33 denied and um maybe also consider its social commun communicative Dimension well um you want to bring the math perspective well I want to bring something in maybe I'm um I'd like to look at the first uh question which is so fundamental here it says what about the universe and how do

00:15:04 we know it and um I want to start off by by a Jewish joke which may not be so funny but um but I think it illustrates something about this and that is um you have um this two Disciples of two famous rabbis and some God for little town in Poland and one of them is saying they're saying how wonderful their their

00:15:35 teachers are and one of them says um I know I know that my teachers Alo yes the mic doesn't work I'll speak louder okay anybody can hear me the mic is not working is working well anyway um maybe if I speak louder everybody can hear me he's going to check the amplifier I think I'll speak louder okay so

00:16:07 um there um he says I know that my Rabbi absolutely incredibly and miraculous person he just uh it's it's just wonderful what do you mean what's the wonderful what did he what's what he says I mean many many things but just last month just last month we had this one we had this remarkable thing happening here I'll tell you what happened we were at our daily prayer and suddenly the rabbi in the middle of the prayer

00:16:38 screamed out and said this is horrible this is terrible the chief Rabbi of Prague has just died he's just died in the middle of the service he had collapsed and died and everybody was shocked and they immediately organized the party to get there for the funeral which has to be done very quickly so they got some Horsemen six Horsemen and they were riding can you imagine they were riding day and night

00:17:09 and everybody was praying that they could make it and amazingly Enough by Dawn they got all the way to prag and it was just wonderful and I said well but that's great now that they so they actually got to the funeral say well um it turns out that the rabbi didn't didn't really die it was fine so he says so what's so what's so wonderful about that

00:17:40 says says you idiot you don't understand anything it has nothing to do with whether the rabbi died or not it's how far this great man can see so uh I think that that I I think that this is um my opinion this is a very U this this all this matter that we are um we're trying what what is knowledge I mean we what do people know

00:18:12 this this disciple knew his Rabbi he was a wonderful man andic it was the amplifier was your microphone okay so um what what is it that I mean this this fellow knew knew his Rabbi very well and KN know everything and he was an intelligent guy and he knew that he thought that he was a great man for many reasons and here was one of one of the examples he saw all the way

00:18:44 and uh somehow things didn't quite work out at the end it's a small thing a small experimental kind of variation so um I think I think that um uh knowledge is something what we know is something very tricky what what is it I mean we you know you you pick up a phone and you hear somebody speaking and you know exactly who it is why I mean the um his voice has been cut up into millions of pieces a lot of and there's something

00:19:16 about it that you know the person there are lots of things that you that you sort of know in some kind of way uh which you can't really verbalize or even uh write down um it's uh I I I would say um there is um so you you're in this we're sort of in a kind of a fog and we have a way of perceiving certain signals and then we say think we then we have to our psychology tells us we have to feel that

00:19:48 we know something you know we we sort of feel that we you know we know very well that we're going to die very soon but we somehow feel extend things and we know that somehow we assume on a daily basis that it's going to keep going on a lot lots of things inside us that make us um make us feel that we know things now there is um there's a mathematical component to all this also but I maybe I'll return to that later uh and that is how you go

00:20:24 from knowing some things to knowing something else by Logic and that that I think is a very important thing that plays plays a very important role in every kind of study of understanding things mathematical or not there's that crucial step from going to from one from from um from something from something that we think we know to something else by Logic

00:20:55 and perhaps I'll perhap I'll discuss that a little later well maybe um let me just make it I mean I I think we do want to there there there there's a very difficult question which is both has to do with institutional structures and these sorts of things where you might say how do we know how how is knowledge produced it's how do we get the evidence um as you say recognizing someone's voice can you really articulate um and that may be very

00:21:27 difficult but I I at least want to put on the other side um not to get too lost in that fog because at least you can check whether certain claims things are reliable I mean I'm I'm reminded of the great magician James Randy who would challenge people who claim to know all sorts of things that you would say I don't know um how they know them because they were sort of like or I mean uh you know know extra sensory

00:22:00 perception or somewhat things that that were supposed to be outside the Ambit of scientific explanation and the beauty of it was that Randy wouldn't engage in the question of how how could that possibly work but he could come up with nice experiments to see whether it does work so I remember once someone said they could see your aura right they could see sticking up a few inches above your head and Aura and it had different colors and on the basis of the color you could tell about your personality and Randy said

00:22:31 okay fine and he had a set of boxes set up 10 boxes where the person would stand so their head was just below the box right um but if there was a a 3-in aura flowing out of them however they could do it the aura Seer could see the aura sticking up the top of the box and he'd say okay let's have somebody come stand um and you tell us where they're standing that's a great test right and what you find is that that person actually can't see anything at all so um how we know is a very tricky

00:23:06 question sometimes that we know or that something is good evidence or a way of approaching things is reliable or not reliable we can get at in a in a somewhat more humble way um a lot world would be a lot better if there was a bit more of that but yeah um I think it's quite clear that um there's the experiential and I'm not um saying that they are sort of binaries or they're an opposition there's the

00:23:37 experiential view of this question and then there's the experimental view of the of how we know and there is a welldeveloped scheme of garnering reliable knowledge of phenomena reliable replicable knowledge that certain certifies what we know is there um so I think it's at least we know one way of knowing that is not as

00:24:09 foggy um sort of the scientific experimental observational way and of course you know the questions that you brought up are that this observations isn't entirely object who we are interferes then there's the issue of what a measurement device actually does because you're convolving the phenomenon via the device that you're using to actually study the phenomenon so there's all of that but but still I think as stim pointed out

00:24:40 that we do have one very reliable scheme experimental scheme within science of producing knowledge so you would limit knowledge experimental scientific knowledge no but I think I think that I I wouldn't limit it but I think that there there's at least one kind of knowledge that we understand quite well how it's produced how it's replicated and its complications and its stability

00:25:13 its provisionality we have a whole understanding of how when you learn something new you have new evidence you have many different independent lines of new evidence you revise your understanding of phenomenon so so you know that process within science of generating knowledge and facts is sort of a nice well oiled machine that we understand no I understand but then you limit right now you limit your definition of knowledge uh to the Wi

00:25:43 yeah of the scientific Community trained in that procedure and I guess the question you would want to ask is the limitations between disciplines and communication between disciplines of scientific knowledge production and then I guess you would also want to ask about uh whether you actually want to limit that we all trains right no I mean

00:26:16 um I'm I'm only giving a perspective I'm not saying that you know this is limited in any way um there's obviously other there other ways of knowing and other of knowledge um but I think the scientific one is an interesting one to jump into and to use as a lens to look at the other ways of knowing is because in science there is the issue of limits that come from

00:26:49 intractability I.E the apparatus the methods of thinking that you've developed um are inadequate at this particular time to study um in better detail and the fact that there are different kinds of sort of intractability right so for example we have when you do sort of climate models right so it's quite possible we have models which we

00:27:20 understand well enough including their limitations of what the um average temperature would be um on Earth in 2025 for example however we will never ever be able to predict what will the average temperature be in New Haven where I live on 13th December 2025 or New York for that matter right so

00:27:50 cold there are so there's that kind of intractability right uh and the question is will you be able to build a better model will you get a more sophisticated model or will there always be some fundamental uncertainties imposed by the complexity of a problem so I think the kinds of intractability that you have in science are different from the intractability that you would have for example in other disciplines right so for example you could on average know so

00:28:23 if you look at anthropology right when on average you could probably tell what the diet of someone 4,000 years ago was on average if you have fossils and but you had their skeleton you could you know figure out probably but you can't say what they actually literally ate on a given day right so so that kind of I think crosses disciplines but then there are other kinds of intractability that don't quite

00:28:53 cross and I think that's sort of the kinds of intractability well uh know I uh I certainly agree with what you say but being sort of of skep Mind how can you be so sure that we won't know exactly what the temperature will be 100 years from now I mean we right now we don't know how to do it but who knows maybe uh Tim will come up with some um method where he'll understand exactly how how things work and be able

00:29:25 predict temperature will be or or within 10° or whatever uh you know we don't I mean the inability is depends on we what we have right now somebody may discover some weird thing um which uh you know I mean I've heard um let me give you an example I've heard um student in the 50s I've heard people

00:29:55 uh coming on and people were discussing how it would be absolutely impossible to analyze the game of chess in a kind of a way that you would sort of list the games and make these trees like they do now because there would be such a huge amount of information that you would need that's just inconceivable that you could do that so the only way you could have computers play chess is somehow to emulate the human thinking and intuition and so on and there was a whole um disc

00:30:27 of that and everybody agreed well it turned out that those limits were surpassed and you can do it the crude way of just listing all the games or try to list partially all the games and then and and and now computers play very good chess so um I think that um there is a there is intractability but to predict what it is is is is a dangerous ground right but that inability has to do with enumeration right so it's a quantitative

00:31:00 thing if you can map out the kinds of intractability I'm talking about are sort of chaos right in a complex system but in the nonar system in the end that's the point that um that you can once you reduce things to enumeration uh then you have a chance and a lot of things that we thought cannot be reduced to enumeration can be in fact reduced to enumeration so can never be no of course not but but to say

00:31:32 now what it is that won't be able to in within 10 years is Dangerous Grounds so I want to be I want to be contrary to whatever fine no I mean I I think um the kinds of problems um that I had in mind were sort of problems where you know chaos sets in

00:32:02 and so some small fluctuation can give you a completely unpredictable outcome and and such an unpredictable outcome that you don't you are actually incapable of constructing a probability distribution function of finite outcomes you're not able to enumerate those outcomes in some kind of distribution so I think there are a lot of problems definitely I gave the climate one because I knew that you that's a good one because we know there that there it's such a complex problem and there's so many different variables that we

00:32:34 don't understand the nonlinear coupling what we do know about nonlinear coupling is that the system can get chaotic and therefore unpredictable outcomes which cannot be enumerated well I don't want to P my point I'll just come in here again on the the question of what is it we want to know right what what is it the now it admittedly it might be practically useful to know the exact temperature in New Haven in 10

00:33:05 years on a certain day if you're planning a party um but you know you you you might think you know from another point of view again you might treat that something we will find out that's certainly not a limit to knowledge it's a limit to predictability maybe um but you also might say from a certain point of view of of understanding of comprehension um um if you think you of the basic fundamentals of the system right and you can analyze it far enough to see as you say it's chaotic system it's Dynamics

00:33:38 and this is what people always call The Butterfly Effect right in some systems a tiny little change in the state now will amplify out to very big changes later um just knowing that is a kind of understanding of the system it's an understanding that makes prediction very different difficult um but on the other hand if what you're after is a kind of just general comprehension you might say I'm H you know that that that's fine um even though it doesn't satisfy all my

00:34:09 all my practical needs so again what what the limits are and whether they're limits you know how sad should we be about the limits I guess we ought to be a little a little careful about I mean I I I'll just make one quick comment because dor has started out talking about the sociological factors and so on in there's may be a small danger

00:34:40 of the term knowledge production because in a way you would think knowledge requires two things knowledge requires a theory which is the thing you're claiming you might know or at least have good reason to believe and it requires evidence which is the grounds on which you accept or reject the theory um and certainly sociological considerations can play a big role in and maybe different in different fields about

00:35:11 Theory production you might say theories in a certain uh say literary criticism I don't know a lot about but my impression is approaches to literary criticism the kinds of theories people have produced have changed quite radically from decade to decade um but the the more Theory production seems to depends on sociological considerations the more worried you're

00:35:41 going to be that none of this is going to produce knowledge because um the the the more you can produce just wildly different kinds of theories the more worried you're going to be well which one's right or are any of them right or if the kinds of theories can be pushed around by the this by the sociological situation very easily um what makes you think they're being pushed in a direction to being being correct so whether in certain Realms you think you're even after the kind of thing we

00:36:13 would call evidentially based theory that PRI is after for understanding dark matter I mean maybe some disciplines aren't after that at all maybe a literary critic might say look there's not going to be a correct or incorrect theory of what this text is about we're just trying out different approaches to reading and seeing how we like them and how you know satisfying we how satisfied we feel and that asking for evidence whether

00:36:44 this is the right way to do it isn't even the right kind of thing so there you might have a limitation of a different kind because it's not exactly a truth directed Enterprise but directed at at something slightly different from that I mean I'm not sure how you think about your own field in this well regard uh my my question was uh I I didn't want to assume that knowledge is reserved to one domain say the Natural Sciences or

00:37:15 the social sciences or the humanities my assumption would be that uh a fundamental concept of knowledge is very different in say those three domains with different methodologies and different theories but um I would still say within say science without me having studied Beyond High School science um you have uh in the Sciences just as much

00:37:50 as in the humanities or in the social sciences if you just look at the institutions of Higher Learning you have funding initiatives you have um priorities that are set um you have decisions sometimes at a national level not to pursue a field to drop a field or to revive a field um you have more or less application driven motion of certain field where you

00:38:23 have um the creation of spaces where people can do less applied sciences I'm not telling you anything new but it seems to me oops that's what happened before um it seems to me that continuously as projects grants are articulated these considerations how it will be funded

00:38:53 whether it will be funded how these decision are made play into the articulation of the qu and I'm not the one to to say this um is a priori bad but I think it uh plays into the limitations of that kind of knowledge production as a collective enter and I think it has just as much in

00:39:25 the Sciences in that sense a political Dimension since it's there that the kind of knowledge whether we care about it or not whether this rather than that also needs to be communicated to a general public so I don't think it's an issue of say fashionable literary theories or not but I think it it has to do with how all kind of study is part of a larger social um larger society with its

00:39:59 political implications yeah if I may um respond here I think the there's the issue of what ising what what is valuable to know and I think that's where the points that you make are totally relevant and they are just as valid in science decisions that are taken constantly I mean we all have worked long enough in major universities to know uh that that has a political social cultural fashion Dimension but I

00:40:32 think one the point if I'm um understanding what Tim was saying correctly is that in the humanities and for example with this literary criticism example right there isn't the same kind of scheme for evaluating many explanations or ordering explanations privileging explanations so in science we have the sort of cycle of experimental

00:41:04 verification replication um you know measurement uh empir I mean sort of you know empirical interventions know however you know they're fuzzy in some ways Etc but the point is we have a scheme uh of ordering explanations and for privileging which one which is correct and which isong wrong which you can discard whereas in the humanities you don't have the same kind of scheme absolutely not the humanities are about something totally different different

00:41:35 right so which so the question is that when you don't have a scheme for privileging one explanation over another the nature of what you create as knowledge so there's multiple ways of knowing there's always a multiple allowed right if not knowledge wouldn't even be the key operative term in the Humanities so so I mean I don't think we have a debate about that yeah yeah I think we agree that you know that

00:42:08 yeah I would like to uh raise a philosophical questions since we a philosopher here um do you should want distinguish between sort of knowledge which is sort of restricted to some kind of conscious ious Ness or uh like you have these thinking about these birds that migrate these tremendous distances and know exactly how to go there and know that they should do it in certain things is that knowledge or is

00:42:40 that what look this is okay so yeah this is what you do in introductory epistemology course say find we have someone who speaks a better language than English for this purpose so in English no is multiply amb ambiguous and in German you have V Kenan and Kenan and you call them different things right um so a kind of practical ability which is what the birds have um is a different kind of thing I

00:43:11 guess I should take you freshman course yeah yeah you know a different so so the the the kind of uh uh old first shot at definition of knowledge of the kind that philosophers are interested in uh goes back to a suggestion made in a platonic dialogue of course it's shot down by Socrates as is every other suggestion but that that knowledge is something like Justified true belief right so in order to know something I have to believe it to be true I have to believe

00:43:41 it it has to be true I can't know falsehoods and I have to be justified and then there's a lot of this is what I was talking about evidence what are my grounds what are my you know what what could I say if someone challenged me um to back up right give give reasons for the belief I have that presumably they could share those reasons or criticize them presumably your birds if I ask you why did you take a right rather than a they you know they have nothing to say I can't criticize them um they they have a perfectly good ability and we might be

00:44:13 interested in how they do it but um well a lot it may very well be that a lot of what we do we can't say about anything either absolutely I mean I mean Hume wonderfully you know it Hume made a wonderful true observation about human beings so Hume was looking at the limits of reason of the human faculty of human reason and and H came to the correct conclusion it's a really good thing that humans don't try and reason their way through their everyday lives because

00:44:43 they die what what we do is we rely on habit mostly right we just do things unthinkingly because we're actually pretty bad reasoners I mean um or people people would die watching Fox News right I mean they would just have conniptions um our you know our actual ability to lay out an argument and here are the premises and this follows from that and this could be questioned is is is is is very poor and and we usually don't rely on that getting around day-to-day life

00:45:14 good for us um it would be nice to promote a little more of it but but I I wasn't very clear cuz before you came Peri was saying about what limitations there are at least in terms of cosmology with your comment about prediction your implication is there is no limitation it's just that we cannot predict now so in 20 years we may be

00:45:45 able to say yes the temperature will be 62 F in September 19 whatever 20 I firmly believe that there are very strong limits extremely strong limits what we going we going just I mean just even in simple things uh which we can't enumerate they get to be so L and so on so very strong limits what I don't believe is that one can a priori say

00:46:16 what those limits are now in other words uh yes I agree that there there are limits and there are questions that we will not be able to do but I to pin down and say and to pin down and say exactly that in 10 years we will not be able to know this and that okay I if you say tomorrow we won then I'll say you're right 10 years maybe 100 years wouldn't thereare yeah I mean this right what

00:46:48 what the limits are on what we may be able to predict depend on the Right theory now you can show some things with some simplified models so that you know you can you can show something like this and this is just now mathematics it's not real physics suppose I had a box of gas and I think of it just like colliding billiard balls so they're just going to bounce off each other in a nice elastic way and if they Collide slightly differently they'll bounce slightly differently so you can just model that system with 10 to the 23rd billiard balls bouncing around and in a kind of

00:47:19 Newtonian situation you ask well suppose I I wanted to predict where that particular atom is going to be in 10 minutes and you just move a rock on Mars right a little Pebble on Mars and you sort of calculate that that little change in the gravitational force is going to make this guy Collide slightly off and that's going to make him bounce off at a slightly different angle and that gets Amplified in every collision

00:47:49 and you can sort of say in that model you can show that if you move this Pebble on Mars where this at is going to be in 10 minutes will be completely different and if that's correct if that's the right Dynamics for this system then you're going to say you're never going to be able to predict where that atom's going to go because you'd have to know the exact position of everything you know now now that's something you know we could find out that some systems are like that um and so specific predictions aren't very come back the key word in this

00:48:21 discussion is if yeah I mean yeah if the conditions are and chances are they are that way you'll never be able to predict but we don't know I mean maybe there's some uh uh what they used to what it's called Maxwell's devil or something that's that's cooking up things so that something will happen in a certain way and some great genius or some guy who's very lucky will stumble and find this and figure out um the box that you

00:48:52 presented him which looks like it blah blah blah will actually be be that everything will concentrate in one corner and everybody will die because they can't breathe breathe anymore I mean that you know so I mean I think that um yeah I mean I think that that we can say very safely that there are a huge amount of stuff that we don't know and we can say there's even a huge amount of

00:49:22 stuff we can never hope to know but we can't really pin down what that's what well list but let's give a chance you wanted to ask something before well I was wondering whether I'm the only one who's somehow hesitating as I hear you all debate the limits of knowledge exclusively in terms of uh the ability to predict or not whether I mean the three that this is the

00:49:52 only limit to knowledge or the way you imagine limit because so far we've only talked about it that way or you have only talked about it in terms of the test of the limitations of knowledge would be the incapacity to predict that's the easiest way yeah and and that I find I I think too poor to think about the limitations of human knowledge and so I actually I was going to to ask how else apart from the limitations of uh the capacity to

00:50:24 predict does one want to articulate or think about the limitations of knowledge this is what I was actually I agree with you I mean I I think prediction isn't such such an interesting thing in fact the interesting thing is it's the opposite side um if you're interested like I am on as it were what the fundamental constituents of the universe are and how they work there are cases where you can have two different proposals and then show they make the same predictions right so whatever those predictions are they they're going to be identical

00:50:56 and then you're in a situation where you say well that means I can't decide between these observationally right so these are kind I dis agree with that if if uh you have two systems that in every case will predict the same things then they're equivalent just just a way of saying no I I say yes that's correct well how else I mean what how can they be different if they if they how can you

00:51:26 possibly um have a difference if this if the uh ideas lead exactly to the same results in every case because the the results are just what happens at Large Scale so Oh I thought you you said every case well but what I mean what you could what it predicts in terms of what's observable which is all we have right yeah right so for example there are string so if it's not if it's not observable if there different is predictions are not observable what what

00:51:59 sense does it make you can't you can't observe it uh you might like to know what it is right no so for example there are various versions of string theories different versions of string theories yes that um will lead to the final post big bang universe that we do see right to the same universe that we see so we don't know how to discriminate between those two the because we because these theories uh it's not clear exactly what else they predict or don't predict

00:52:30 there are sort of iffy theories but if you have example of two theories where you can where where in every case what they predict the same thing that are observable then I claim the theories are equivalent no no no but I'm giving the same example so the the theories predict observables that are exactly what all we observe in the 13.8 billion years after the big bang the point of discrimination

00:53:01 between these lies Beyond right and we have no observational consequence that effect to discriminate between those two theories and they are fundamentally different theories they are not the same Theory so we we cannot know this is a conundrum that no but but I guess we're not talking on the same I I was I was uh

00:53:33 assuming from his comments that we already that we already know what all these theories predict and and everything they do is the same but you're saying that these theories we don't really know they're different you don't really know what they will predict in other all all the things that we know they are the same but there may be some place where one Theory says one thing and the other other says something else some you know not all that's a different situation this is sort of the wrong way around look the theories that PRI are

00:54:04 talking about are different theories how do I know that well they say different things like they say the exact structure you have all these compactified cabay Yao spaces with different topologies and this guy has this one and that one this is a different Theory then you subject it to some analysis and say wait let me finish then you subject it to an analysis and say what does this Theory predict now there is no logical reason why two different theories couldn't make the same predictions well it depends what you mean by

00:54:35 different I I they say different things no if they predict exactly the same things in every conceivable circumstance they say the same thing except maybe in different language well this is you know as I say you you you say SpaceTime has 10 dimensions three three of them spread out seven of them are compactified you're a mathematician I give you different topologies for that compactification those are two different theories of space time structure no they aren't sure they are they're the same

00:55:06 things they're not different topologies is this a is this a limit that no you can't have two theories no I think no no this is I think what we're alluding to is a very interesting conundrum and limit in cosmology again restricted to cosmology which is the fact that um you we we do not have a theory pre big bang that we can get observational evidence for so we cannot

00:55:40 pin down which theory is right we can't use the same methods of evaluation of the truth value of theories that we have become accustomed to and we cannot discriminate between them so what so the so how do we determine what is more valid than which which model is more valid than the other because the predictions that these theories make are always late time predictions and they patch on to everything that we do see so

00:56:11 you know we don't have anything that's can be used as a discriminant right so it's a new kind of explanation so you know this is idea of a Multiverse right for example um um these are not testable theories so in cosmology we at this very interesting juncture but we've reached a point where we may have to start permitting other kinds of explanations Beyond testable observability and so on so

00:56:45 forth and you know maybe he's right that maybe in 10 years someone will come up with an observable consequence today in uh the night sky in know in the cosmic microwave background or something of two different bubble universes colliding and we will know I mean maybe no uh yeah I I'm just saying it's I'm something I'm just saying something completely theoretical which may not actually apply that's why we have I'm saying that if by chance two theories in every case

00:57:15 predict exactly the same thing then I say the theories are equivalent but as it is all these theor that you mentioned uh we don't really know what they predict in some we know the things that we they may agree on the things that we know but it's a very limited range there lots of things that this we haven't mathematically or whatever we Haven been able to use these theories to predict so they look different they may well be different because they at some point you may turn out that they do predict different

00:57:47 things but if you are sure that they will never predict anything different than their equivalent my in my let me give you again go back to to philosophy SK introduction to skepticism do do we know back here's here are two theories that are different one Theory says this is what priia will tell us that there was a big kind of big bangy event that was what 13.7 Are We Now a billion years ago and there was all of this uh Galaxy formation and then

00:58:18 the Earth formed in the solar system and there was a lot of evolution then we have another theory it's really quite a different Theory it says this um the universe only began to exist 10 minutes ago none of you you you none of you actually got here by Subway or anything like that um it it just began right by Fiat in exactly the state that we think obtained 10 10 minutes ago but there was nothing before that right so you've got all these false memories it's going to be okay when you go home everything will be right now those are

00:58:48 just different theories right one says you grew up and the other says no you didn't right you're under this kind of strange delusion of having grown up but clearly by construction they make exactly the same predictions for everything you could possibly observe from here until Infinity because they they make the the physical state match as of 10 minutes ago those are different theories now one is silly okay I'm not suggesting you believe it but your reason for not believing it is not

00:59:18 anything You observe it's something else well but I mean uh it depends what you mean by Theory I mean you want a theory right I mean if you if you say something if you stick on some kind of irrelevant stuff to a theory and then say that makes it different and has nothing to do with with prediction or anything else then then you say okay that's different but actually it's the same thing if it predicts the same thing I mean you you World War II never

00:59:50 occurred but I think his point was I thought your point to me at at least not being a mathematician or a cosmologist or a philosopher made sense that it may be that those two theories in addition to what they predict which is the same they could also at some point you could also find things that they predict that are different yeah sure but the question and therefore if that then they would be different but if for some

01:00:20 unknown theoretic that's what I'm saying but if for some unknown theoretical reason you can show that two theories will predict always the same thing then I claim that they're equivalent in my definition of equivalent may not be your definition you may you may feel that if you add some irrelevant thing to a theory then it makes it different I say that if if the theory if the theories are the same for all relevant things then then for for me they're the same the differences between the theories happen in a regime where our methods of

01:00:53 observation testing blah blah blah don't apply that's the case we are talking about it's not that you know one of them is just ridiculous because it's different the thing is you could have two theories that are very different theories whole set of predictions they make a set of predictions that are identical and accessible with the apparatus we have the experimental observational that we have they make predictions that might be different

01:01:23 let's say they are different they are different but they are different in a realm in a regime that our methods of evaluating theories are not applicable not accessible no have no no argument with that yeah I think those are the kinds of theories I just picking up something that he said perhaps misunderstanding it that if they are exactly the same on every conceivable experiment that you can make then I say they're equivalent that's but that's not what you're saying I agree with well I think I want to go back to

01:01:56 um bringing dth into the conversation about kinds of explanation that constitute knowledge uh and so and they are fundamentally different across disciplines and I wanted you to talk a little bit more about um you know in in science it's kind of there is a mechanism of figuring out what is a valid explanation um what is how does that map into other

01:02:29 fields how would you think about it in other fields you obviously are not ordering there's no hierarchy of explanation there isn't one you know um critical view that is better than the other there's no uh you don't have a mechanism or to generate you know a hierarchy of explanation to say this is better than that that's better than this but there is something else I mean still there is a way in which people are able to feret out the Absurd from the

01:03:01 profound and um and you know it would be interesting to hear a little bit more about how the Discrimination happens in other fields it's kind of easy to see how it happens in science well I mean what you described in science works very much with a model of um figuring out and representing MH the laws of nature So within I mean in a very abstract way within a representational

01:03:32 paradigm and um I would say you mean Beyond mathematics not okay yeah um with the empirical component and in Humanities I mean which is also historical phenomenon there were no Humanities before the Renaissance but in the humanities what you stud study is not primarily nature but I would say the best products of the human mind as they I mean arguably best product human mind

01:04:05 as they emerge in the Arts as they emerge in philosophy in religion and um what we study is what allows for their emergence but also how we make them relevant to our time and what we produce is not primarily knowledge but we ac we expect that this engagement with what I would call the best products of the human mind which is always

01:04:37 mediated um transforms the student and the teacher so it's a very different activity so of course there are hundreds of years of procedures and ways of deciding and evaluating the validity of that kind of scholarship absolutely um but it it's not within that frame of a kind of representational factual empirical set so limitation

01:05:07 doesn't play a role at all well the limitation plays also a role but the limitation there I think has to do primarily with historical situatedness historical cultural situatedness which is a limitation that you know you can turn around you can make productive and in a way when I address the situatedness of scientific knowledge I was interested in hearing you talk more and you did talk quite a bit about

01:05:39 making the limitations productive MH uh rather than seeing them as a disadvantage and say in the humanities it's I don't think a model of a cumulative uh yes Enterprise and I I was listening to the three of you and I found it especially interesting with some of the remarks that Tim made you also portrayed in a way scientific progress not as a

01:06:12 cumulative uh Enterprise but as a synthetic um Enterprise or it's both right any way well I'm can you Des you address the question of the reduction of the increased complexity which then raises the question of the reduction of complexity yeah I guess the two alternate yeah but so I guess there the limitations would be articulated differently with regard of to how you

01:06:46 see your entire field and its limitations if you say the scientific versus say the get scholarship in the humanities I think scholarship in the humanities at very fundamental level always has to do with different histories and the present and how you bring them uh together whereas in The Sciences I don't think this is the primary limitation which you can make or have to make productive but you

01:07:19 know you you talked about the observation and the limits to predictability and I would assume there are others yeah I I mean let me just say the I mean the sociological you mentioned before the sociological aspect in terms of funding and so on I mean that that's a different kind of limit very alive in the sciences and in some sense what I mean this comes back to the question what are you interested in what are you trying to find out um at a

01:07:51 certain point there was a tremendous premium on finding out a whole lot about radioactive uranium um and how it works during the Manhattan Project and a lot of resources were put into it and by any reasonable standard of success people were quite successful in figuring out how it work but um there was obviously a decision to focus resources on that question rather than any number of other questions you could have focused on and and probably right now for people like

01:08:23 uh priia um the biggest threat to producing more knowledge my guess is that somebody says why do we care about Dark Matter rather than you know that there are limitations of the sizes and so on and everything and you know I mean that's at least one place where where part of us we're just looking at the limitations the universe itself puts on us in terms of what we can know about it um there are probably much stronger

01:08:55 limitations of the that we put on ourselves as a society in terms of what we demand or or request or make sure gets funded and is allowed you know research that's allowed to continue and that's probably a bigger worry quite honestly practical worry than any of these other ones kind of abstract ones we've been talking about okay questions questions no comments if you have

01:09:26 comments you write them down I think so we all don't want to be driven by the applicability issue right but you know I think that um important point that you made is that science has invested in a notion of progress in a way that the humanities are not because there's a provisionality in science okay couple uh quick observation my question um I'm going I I submit that the one possible reconciliation between um uh Joseph and

01:09:59 the priia Tim camp on the uh on the matter of the theories uh it as you know U originally there were multiple versions of string theory uh five of them Ed Whitten uh you know famously resolved them in a very short period of time to surprise his fellow confires so I'm s you know one possible way out of that conundrum would be that at a deeper level of mathematical structure they would found to have have more in common but it's also a question of we can't

01:10:30 know what we don't know to to the point of since we can't there's some tantalizing possibilities but we can't go back before the Big Bang so there are axiomatics assumptions made that those different assumptions affect the theories that come out of it and it is remarkable that they predict the same end state so I just wanted to mention that uh the but the question is um in terms of knowledge production we

01:11:02 focused Prim uh on cognitive production of knowledge um and mostly in the Sciences we didn't really address very much in the Arts and the question my question is based on Wilson uh biologist will know uh that um science explain emotion um and art communicates it communicates emotion so the question is since our um cognition is primarily

01:11:34 driven or largely driven by emotional and other cognitive biases of which we are not necessarily aware um and that rational explanation is often an afterthought I'm wondering if there's anyone who has any comment on that that whole portion of knowledge that is partially brought brought to the table by um phenotypical expression in neural tissue like for example in the ascending visual pathway and the cub and weasel Discovery but also uh in terms of

01:12:06 interesting experiments that show that a a choice experiment uh can be predicted by the researchers by monitoring the the lyic system with fmri they know the decision the subjects will make before they use cognition and language to make that decision if anyone has a comment on that entire realm of knowledge I would welcome it I I mean I I'm not deeply knowledgeable about this fmri

01:12:37 things but my understanding from what I've read is that is that it's a bit overblown when people say oh uh you know we evil scientists looking at our screens and monitoring your brain know what you're going to do before you do it um in that those are typically choices which are literally random I mean what you think of as random choices right push the button on the right or the button on the left with no particular reason to to to care or be able to

01:13:07 consider which is the better choice right and that of of course something's going to happen in your brain that's going to make that as it were decide which way you go and maybe they can pick it up but but the kind of choices we care about are ones that we consider right ones that we uh reflect on and deliberate about and you know that that's not even what they're looking at so if you were to if you were to if you were to ask me a question

01:13:38 about that required a lot of deliberation where where I thought a lot hung on what I did and it was hard and I had to evaluate and make guesses and so on I don't think anybody looking at an fmri is going to tell me 10 minutes beforehand or 5 minutes beforehand how that's going to come out experiment so your position there's evence and in fact it wasn't just a random it was a decision they were to make a conscious decision about a particular uh fining choice and so and that was predictable

01:14:08 with with high confidence by the activity in the how that decision making is done chemical molecule by molecule by molecule is not known right so I just want to come back to IO Wilson right I think he is overly optimistic so I think his point of view is that you know the things that are currently unknowable are things that are in the the things in the gaps are between disciplines and he's very optimistic that we will know in X

01:14:43 number of years we will know what is the molecular composition of anger like what will you know what are the things that need to line up that will make you angry wait wait right he believes in [Music] that okay you can have the discussion have you finished pleas I'm done um if one accepts Evolution and that we our mind and brain has evolved over the years and that we

01:15:13 realize monkeys can't understand the world why don't why is it obvious that some species will come after us with bigger brains that we're not the end of evolution and they'll look back at us and say obviously those species couldn't understand what was going on yeah there's nothing I can respond other than I think as a species we seem to be so stupid that we'll destroy the planet before there's room for you know the next set of emergent beings I mean

01:15:44 let me just say say one I mean people often say that look we evolved to survive on the Savannah um that's you know the context now humans as you know unlike every other species that's ever existed the premium for intelligence in humans became critical that's why our brains got so big right they got so big they got as big as they could get until it would kill you to give birth to a thing with such a big brain and that's why we have

01:16:15 such a long latency period as infants that we can't take care of ourselves cuz basically we're still essentially growing outside the womb to get our brain even bigger so we're pretty much at the biological brain limit but the interesting thing is is that that pressure for higher intelligence does not occur in any other species right cockroaches have been around a really long time they don't need to get smarter they're doing perfectly well they're going to outlive us okay so there's whether whether there will ever be a more intelligent species is one question the other question is are we really that

01:16:47 dumb I mean the argument that says we grew up and we we we were selected to survive in the savannah would predict that why should we ever understand the microscopics of a table right just the microscopic just the the chemical structure the double helix structure of DNA why should we ever understand a supernova why should we ever understand how galaxies form I mean all of things that are vastly outside the scale or a lot of mathematics right why should we understand complex numbers you know so

01:17:18 the range of things that humans have been able to understand that have no basis obvious basis at all in evolutionary history is really quite astonishing yeah but there are other things like understanding beginnings and ends that's sort of built into our basic you can't you can't conceive a things without Beginnings or ends or what comes before the beginning what comes after the end there c those Concepts like that seem to me I don't think we're ever going to understand anyway um yeah I

01:17:49 would like to comment on something Tim said um yeah I it's well I agree with everything there's one uh thing is that we have had this tremendous evolution in in being able to understand more and more is taken place maybe in the past 50,000 years before that things were going rather slowly so it's very speculative thing if there's a if there were similar conditions as we had experienced and similar humans exist

01:18:21 somewhere else but if they had a 1 million year advantage over us uh what sort of things there there I mean if their rate of development shoots up at the same rate as ours and continues uh they may be so far ahead of us that we look pretty pretty primitive uh well I'm in the Arts I'm a painter and art historian and so I'm going to speak up a little for the other side um what interests me in the in the

01:18:54 Arts is there is a difference in science between knowing and in the Arts between creating and the concept creating burkson by the way speaks very well about a fluid Universe where one thing happens after another and you have no idea what's going to happen because each thing accumulates after another thing and in the process of creating whether it's in writing or in painting it's a proc the exciting process is you do not know what is going to happen after you make one stroke and another stroke what the nature of that procedure is going to

01:19:25 be and that doesn't just limit itself though I think to the world of the art I think it limits itself I mean it expands itself to the freedom and lasticity of the mind and artists are very often interested in the interior and exterior world but maybe even more so now in the interior world what do we know before we look at the world what's already inside us do we already understand structures without uh without looking at the external worlds so there is a conflict between what do we know internally in

01:19:56 our very brain structure what exists in the outside world how do we mingle the two and how can we the the great excitement in the Arts is creativity is the unknowing and finding out where you are finding a position where you are so instead of looking for certainty there's a search for where will I go will I will it lead somewhere I've never been before and I think the these are very important questions maybe in the larger sphere too

01:20:26 about the excitement of unknowability rather than certainty very nice um very nicec um I just wanted to quickly add that you know even in science there is you know there is provisionality it's a different kind of provisionality where you you know what you know now and that is subject you know our current best understanding of something could change dramatically the means by which it changes is very prescribed it's experiment it's evidence

01:20:59 and it's different for the Arts it's provision the the way in which the provisionality shifts is different and it's part of a what you call the creative process right and I should leave you to comment more on this is beautifully said doesn't need any comment okay okay uh first a observation and then a question uh the observation is this gentleman uh sort of challenged the butterfly effect is that a true uh

01:21:29 aspect of uh chaotic systems and it made me think of uh something recent discovery of uh a holographic universe that this 3D the information contained in the 3D Universe which we think is 3D can actually be mapped into two Dimensions So Physical phenomena may be slightly more more ordered than we think I don't know if that's relevant but that's an observation that maybe you're on to something there uh and then the

01:22:01 question uh is about uh world of policy and decision making that we make as individuals and we make as a society before the uh economic collapse of 2008 uh no one quite saw that coming was that a lack of knowledge was that a butterfly effect or was that truly we were blind to something that we should have known and if affects today I mean what's our policy with respect to

01:22:34 Isis and Ebola and all these other threats how real is the Isis threat how committed are our allies and enemies how do we know these things uh so is that part of this discussion or are we just concerned about Art and Science as far as knowledge goes I think what you address is a very interesting question in terms of how far

01:23:07 does the scientific Paradigm of knowledge get expanded uh when we go into the realm of uh politics is uh I don't know whether I can say this loud here but is economics science yeah oh that's another debate you can say it loud yeah no but when does it and how does it pose as a science and when is it a form of politics and

01:23:40 um so I think that's that's the question about the limits of the scientific Paradigm which is I think a very relevant political question that brings up again the question of about the interests the way relevance gets articulated and debated in a Democratic Society if the resources are limited right I mean I mean I would say in the in the particular case of the financial crisis uh it's not so much the

01:24:11 limitations of Economics as a science it's just the imposition of unbelievable amounts of self-interest into the system I mean you know Ponzi schemes it's economically well understood that Ponzi schemes will collapse it's also perfectly well understood that they make a heck of a lot of money for certain people over a certain period of time okay so a self-organizing pony scheme in which uh a bank can sell somebody a mortgage and

01:24:42 then immediately throw it off on some other bank so that if the thing goes bust they're you know they're secure I mean this is just an opportunity for people to make tons of and tons and tons of money in a way that is foreseeably not sustainable and will eventually yes is it foreseeably was in 2006 did we foresee I think yes I think it was perfectly foreseeable and foreseen and still people were making tons and tons of money off it I

01:25:13 mean you know the question is not g could you not see it coming the point is even if you see it coming lots of people are going to say yeah and somebody else is going to get stuck with the bag and I'm going to make a ton of money off it okay and you you can't no amount of economic you know economics will tell you that's actually what's going to happen I just add to that that in fact the people who were after the money were right and in the end when everything collapsed they didn't lose the money that's right the the banks were bailed out they got every and everything went

01:25:45 uh so from their point of view if they're interested in making the money they were completely right and economics was a very sound science given the fact for they understood it and they wanted to get their money and they didn't care about anything else so um so it worked very well and shows that it is a a viable science I just wanted to sorry you want to say something well I know I I keep that for another point the um I wanted to quickly respond to your uh question

01:26:15 about you know the relevance for argument to threats and risk and managing risk Isis Ebola and so on and I think there is relevance because you know what we're talking about um is extrapolation from what we know however little it might be and what those extrapolations are and the degree of confidence we have in those extrapolations so you know there are models that predict now how Ebola will spread with a certain degree of

01:26:46 confidence for example so indeed the ways in which we are thinking about this that has to do with extrapolations of current knowledge and the limitations that it imposes in terms of how reliable those extrapolations are is very relevant and it's very policy relevant um and I think you know my former advisor is now started in uh with a bunch of people in Cambridge an Institute for the evaluation of existential risks it's um Martin Reese

01:27:20 um so you know they really work within you know trying to estimate the probabilities for right I I mean I I do think practical situ there are cases like you say so take Ebola could it become airborne if it became Airborne you're in an entirely different epidemiological situation very dangerous extremely dangerous there limits to what we know and what the mutation rates are and what the probabilities are but on the other hand

01:27:51 if like climate change it's not that we're in that situation we're in a situation we have tremendously good I mean there's you know always issues around the edge um there are systematic attempts by people with a lot of money and a lot of power to avoid doing certain things because it will hurt their bottom line in the case of Isis I mean my God one of the suggestions what's the first thing we have to do about Isis secure the border with Mexico right I mean this is not you know you shouldn't be having a discussion about the limits of knowledge here you should I mean this is just you

01:28:22 know fear-mongering nonsense that a bunch of guys with you know rifles are going to be coming across the Mexican border I mean so I just want to quickly give a plug for a new film that's coming out called merchants of doubt and it's about this uh historian um at Harvard Naomi oreki uh talking climate change and she's done a study showing that more than 97% of scientists actually agree on climate change and we know how in

01:28:54 popular culture it's presented as an ongoing controversy right so okay uh this question is directed towards the scientist possibly the philosopher scientist a little louder can you hear me yeah that made a difference uh so uh earlier Dr Nat nataran uh pointed out that there seems to be an agreed upon limit uh pre Big Bang uh my question is uh

01:29:28 given that you're all curious um empirical reasoning often atheistic people I'm talking about scientists uh how do you deal with just that stoppage that that just oh let's forget about it let's just not talk about it and maybe you have some insight on personally or with your colleagues you can talk about someone else well it is problematic right and

01:30:00 and I think that so for example let me give uh an an example of um because pre big we don't have information and we have these theoretical ideas floating around and then post Big Bang we have this additional conundrum that you know there's depending on who you are there are about six numbers that will describe the fate of the universe the future present and the past and they are measurable and they have particular values the question is why do they have those values and so there's this whole

01:30:30 sort of there was a whole argument of why does our um Universe seem to be so tailor made why are it so finely tuned right and so one way out of this finely tuned situation was to say well let's say there are six numbers that determine the fate of the universe and let's just say that there's some probability distribution function for the values all possible values of those six numbers there are many draws from those there are numbers six six draws infinite number of six draws and each of them gives you a universe so to someone like

01:31:00 me that's a very acceptable so that's a Multiverse so that's a very comfortable explanation and an explanation um which is not going to be empirically testable and as I said and the discomfort there is do we then have to start thinking about new ways of evaluating explan competing explanation right uh and I think it's something that's uh scientifically quite actively debated wouldn't you say Tim on both on philosophical grounds and empirical

01:31:31 grounds um in terms of like an is this what's the out right I mean that's what you're asking right what's the out right you know yeah I mean the the only thing I would add is there's a kind of presupposition behind your question I don't know what atheism has to do with anything that well what can we do if we want to know something but the evidence isn't available to answer the question we're interested in how do we deal with that and of course that happens all the time in life and lots of things I mean there

01:32:02 are people who debate who wrote Shakespeare's plays and they have these different you know possible people will there ever be evidence I mean there's been all this dispute who was Jack the Ripper I just was reading recently they think oh gosh there was a piece of evidence that was overlooked some Shaw and it had this DNA on it now we know it was so and so maybe that's right maybe that's wrong maybe that sh would never show up I mean there are lots of questions out there that you might have intense interest in if it turns out the evidence isn't there to to answer the question you're interested in you know

01:32:34 look you're disappointed okay suck it up that's life I mean you know you do your best right you try and look you try and look at all the possible avenues for acquiring evidence and if you run into a roadblock and it could be a roadblock of deep physical principle or it could be a very trivial one right that just that Shaw got burned up and it's gone um if you run into a roadblock you run into a roadblock and you just get on with life I don't know what to I don't think there's anything very deep to say about

01:33:08 that in the beginning you said um in the beginning you said that you didn't have a reason to believe that the human mind is Limitless and that got me thinking um do we have reasons to believe that our minds are rational so my question kind of flows out of that like it's a foundational question what is the philosophical foundation for one human beings humans being able to understand the universe mathematically and then two the universe in actuality being mathematically

01:33:41 intelligible it's kind of like the evolution question before is there a foundation for us trusting our rationality and then um H how is it that the universe is intelligible I think that is what is truly amazing um that a that mathematics is such a potent and fundamental language that enables you or a system of thinking that enables you to understand so much of the universe and why it's intelligible at all I think is um I I

01:34:14 think it's that's the wonderful mystery and it's a source of Wonder and awe and I I don't think that we have a deep understanding at the moment uh one of my colleagues does have a book that he wrote Max tegmark um recently um and he attempts um he makes the claim that mathematics is much more fundamental in a way to it it underlies everything in the universe and that's why everything in his opinion is

01:34:45 intelligible with mathematics I'm not sure I'd go as far as him but um that's one place to see what what you think what does the mathematician think well I I think I think somehow that mathematics is the right um way of understanding a lot of things that happen in the world and it's you know just like U just like if you try to use ordinary

01:35:17 language to explain things uh the things will be things in ordinary life are not so uh don't don't have connections which can be expressed so so well in order language so if you try to uh for example describe some fairly simple things in in some subject like differential geometry which comes in in in string theory and so on if you try to uh describe that in language it becomes so uh convoluted that you can't even even start so I

01:35:50 think mathem matics uh is the sort of the natural way to try and think about a lot of phenomen why I don't know I mean who knows it's a mystery but but it seems to be um I mean what what how do people how do people communicate how do people uh write down facts things to fact so so what we know is we know how to writing started by writing down by

01:36:24 speech first and then you try to reproduce speech and the language and so on and um mathematics uh is a is that process which where you are trying to describe certain phenomena and these phenomenas are even even in things that you may not consider science like economics uh it becomes uh very hard to express certain Concepts without using uh mathematical the mathematical yeah can I just make a

01:36:55 short comment here because I think um the Greeks divided mathematics we talk about mathematics the Greeks divided mathematics into geometry and arithmetic arithmetic was the theory of number and geometry was the theory of magnitude um over the course of time in mathematical physics the number part the algebraic part has gotten bigger and bigger and bigger and in a way the geometrical part kind of smaller and smaller and smaller contest there okay but but certainly most of most of physics books you're

01:37:26 going to have a lot of algebra in it okay and you're using complex numbers and people ask why complex numbers and things like that but if you were to ask why is geometry if you go back to ukan Geometry why might that be a good way to represent the world the answer was because it's has a geometrical structure just straightforwardly has a geome geometrical structure Galileo said you know the the language of geometry was circles and triangles and so on because he thought were such I'm I'm not an expert on Greek but I have a feeling that geometry meant something else than what you mean by geometry I think it

01:37:58 included algebra what there was it didn't that's part of arithmetic that's the comicus I I do know GRE what do you think uid elements is what geometry or GE it's geometry with with one book on the theory of proportion which was held in common between arithmetic and geometry sorry this is getting technical um so anyway if you think this way you might say I'm all of this is a plug okay that's coming up if you think this way you might say what I'd really like to do is get numbers out of my mathematics and

01:38:30 and um they they mentioned my book new new foundations for physical geometry that's just what that is it's an attempt to get numbers out and then you understand more clearly why the mathematics applies to the physical world I I I I think that u in my my estimation these divisions uh that exist you say geometry and algebra and Analysis and so on those are topology I don't know what uh those are artificial

01:39:02 uh divisions in in my view and I think that all these things are very much intertwined I don't think uh you know for example uh I don't think you can separate number Theory from analysis or from geometry orry or for differential geometry one flows right into into each other and uh uh you know I I I see that happening all over I mean and uh you know people who are really mathematical minded like like Whitten is just as

01:39:34 interested in in number Theory as in Geometry as in as an analysis and it all sort of flows together and in fact uh some of the some of the great discoveries that come out of string theory were disc matics which were not I I don't know I am not so completely convinced about don't understand what what the discoveries are in physics but the ones in mathematics are spectacular and they were discoveries in number Theory discoveries

01:40:04 in geometry and it was all intertwined and it was all intertwined with analysis and I and the uh whole development of complex numbers comes from geometry or you could say and many developments in Geometry from complex numbers etc etc I don't think you can you can uh artificially say this is numbers this is it just doesn't work that way in my in my estimation okay so I have two questions

01:40:34 one for Priya uh what do you think about the um believability of the recent evidence on gravitational waves supporting the Multiverse Theory and um not secure enough to be considered even even a detection so she's not secure enough so there there was a claim that gravitational waves the detection of gravitational waves would support the Multiverse Theory not talking about the

01:41:05 detection of gravitational waves supporting inflation Theory which is correct and what is disput measurements what's disputed is how significant that result is and that will get settled in a couple of months when many other experiments will be able independent experiments should see or not see it because that's an issue of the model as well as how it's tested so both of those yeah no I think the there isn't uh enough scientific consensus on what the potential

01:41:39 observational signatures might be of the Multiverse my second question is to all of you regarding the politics of the peer review process in production of [Laughter] [Music] knowledge the politics of it politics of peer well I'll just make a real quick it's because I work in different fields in philosophy everything's double blinded everything double blinded right

01:42:11 so you don't know as a referee you don't know who wrote the paper uh it's it curious cuz in physics it isn't because people have to refer to their own work I guess so often that it's not really practical but there you know you you can try and limit uh peer review I mean bias is coming into peer review through certain mechanisms like blinding and uh you know it is done and it has made some difference so one

01:42:44 asive that so whenever it is an explosive idea that it it is lot much harder and people who are you know already in the field will resist it yeah to become a part of the existing body of knowledge that's a great a that's a great aspect of it and I think that's um it's a very um pertinent question because you know it some of it has to do with the practice of science and how science is now being

01:43:16 practiced it's no longer the sort of Lone individual thinking great brilliant thoughts and writing these papers right it's a group Enterprise and then there's a Turf there's a definition of turf now because they are groups and because it's funding it's all the things it's the situatedness of how is created which is very very important and the way that impacts in my opinion it's not good for science to all become big group science big science as it's called and I think we need different models of doing science that need to work at the same

01:43:47 time and I totally agree the one of the one of the sort of casualties of big science is that it's science by consensus so there's not as many creative risks taken and therefore if someone takes a creative risk it's harder um to actually make an impact yeah my question is directed at Dortha uh earlier you seemed a bit saddened at um when prio was talking about scientific knowledge and and it

01:44:19 made it seem as if that was the only knowledge we cared about and you you you implied that there's other knowledge other types of knowledge which were important to you I understanding that there's more to just the humanities than just knowledge what other types of knowledge are relevant to you I I I linguistic knowledge like what does it mean to understand a sentence came to mind but but is that the sort of thing you're talking about um I think I should clarify something I wasn't sad

01:44:54 and I I have no science envy and uh nor science suspicion or problems with science um that's why I try to the disclaimer that's why I try to delineate uh how I understand that uh The Sciences um do something very different for from what people like I do in the humanity say I articulated it by

01:45:26 divisions uh Sciences social sciences Humanities and um what what you picked up as maybe a frown on my side was not uh against science or against priia but uh more a doubt and the direction in which I kind of at some times try to steer our discussion was when the scientific model of knowledge production and also Authority

01:45:59 becomes the dominant one in political discussions that's not the fault of scientists but when um what I would think need to be deliberated in terms of procedures values Etc get uh articulated as if it were issue of more or less clear scientific facts right that I think is uh the problematic area and that's where I

01:46:29 would criticize um it's not the fault of the scientists but the uses of an often rather reductive model of scientific knowledge in the public domain as the exclusive model of knowledge yeah thank you for that last question it's kind of related and um along how to control that then what you just expanded on the misuse of uh science or social science and also the

01:47:01 uh the other part I was grinding into was expanding more on U what kind of schemes you can place in there so you can differentiate the hierarchy of explanations well I mean then I guess the question is in what domain I I found it important but Priya said the issue say if we look at just research institutions already there the question of

01:47:31 um individual structures and how much do you have actually the huge conglomerates of collective research uh and individual institutions dictate priorities Define relevance that I think can have a very negative impact on science but also on other areas of learning and inquiry um yeah I think if I may comment

01:48:02 briefly on um you're talking about sort of the policy makers adaptation of and um of of science I think part of the problem I think arises my personal opinion I mean arises from the fact of a misperception of what science is in the public domain I mean and I think scientists are partly to blame for this uh but not entirely uh there's this notion that science is offers this sort

01:48:33 of way to derive fixed truths from nature it says machine you're you know you're churning out these fixed truths um and I think that is not in the service of um public good I mean good policies etc etc May mainly because that is not what science is science is messy the process is messy and that our the way our understanding uh proceeds is you know that it's provisional but it's supported by data and evidence and yet it's provisional so when there's more

01:49:05 data better data more accurate data possibly helped Along by new technologies Etc ET new instruments you know um there is I mean there is a shift in the best current understanding so science is very Dynamic there's a way it's PR dnamic it has uncertainty somehow that needs to be understood by the public better because otherwise policy makers are taking a very simplified view of science has an

01:49:35 incorrect view of Science and co-opting it um for other reasons for you know the the exterran reasons that have nothing to do with science itself but but have to do with the reality of politics and interest self-interests and and so on so for it so I think part of the where the solution lies in sort of mitigating these sort of policy um uh difficulties is really I think it behooves us scientists to kind of explain better how

01:50:05 science actually works the practice of science and on that then between the social sciences and physical sciences what kind of scheme can you make the social science more robust um well I think I think that um you know we can get into a whole debate and I've got into a lot of debates with my Economist friends and sociology friends about um how evidence could be used to make arguments in their

01:50:35 fields and and I think that there are limitations because of the kinds of complexity in the systems that they study I.E human beings and the fact that we are not rational actors I mean you know behavioral economics is cottoning onto it finally and so I think that you know a lot of areas uh of social science you know there will be a shift where there'll be kinds of certain kinds of questions would fall within the purview of the methods of Science and they would be useful but they wouldn't be ultimately

01:51:07 useful necessarily they may not be fully Illuminating and the kinds of things that Dortha talked about which is you know the situation the context um politics self-interest um all of that is much more important can be much more important in many of those questions so okay thank [Applause]

01:51:39 you you know why because there's a whole thing at the [Music] park we got to look at that [Music] other [Music] abely the amplifier was

01:52:12 [Music] a I don't know what [Music]

01:52:47 happens I'm just interested everything uh I was a mathematician and student at one point I've done a huge amount of stuff that is different from what I got my original training in but I keep on coming back to some mostly uh data science you know research you know try to get very specific answers to very specific questions this

01:53:28 I love questions you know the limit knowledge how do you make a decision marry who that how do you know that person how do you know decision obviously how do you know

01:54:14 I still don't know the whole top cover hisory you know it's

01:54:45 also