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Samir Okasha: Philosophy of Evolution
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Samir Okasha: Philosophy of Evolution

Samir is a philosopher of science whose work focuses on theories of knowledge, evolutionary theory and the philosophy of biology.

Samir is a philosopher of science whose work focuses on theories of knowledge, evolutionary theory and the philosophy of biology.

We discuss:

  • The difference between philosophical and scientific questions

  • The limits of human knowledge

  • Progress in science and philosophy

  • Evolutionary psychology and the foundations of social and cultural norms

  • Altruism, Morality

… and other topics.

Watch on YouTube. Listen on Spotify, Apple Podcasts, or any other podcast platform. Read the full transcript here. Follow me on Twitter/X for episodes and infrequent social commentary.

Episode links

  • Representing evolution: https://representingevolution.xyz/

  • Intro to the Philosophy of Science: https://a.co/d/5g1AdqQ

  • Intro the the Philosophy of Biology: https://a.co/d/8HVosfH


Timestamps

0:00 Intro

1:00 The limits of human knowledge

3:55 What is science?

9:00 Science vs philosophy

18:38 Can we make progress in philosophy?

23:20 Philosophy of biology

29:58 Functional language in biology

34:12 Is evolutionary psychology is pseudoscience?

45:40 Evolution and morality

58:28 Can we get 'ought' from 'is'?

1:08:00 Book recommendations


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Transcript

This transcript is AI-generated and may contain errors. It will be corrected and annotated with links and citations over time.

[00:00:03] Matt Geleta: Samir, let's start with a statement from Bertrand Russell, who is widely regarded as one of the most influential thinkers of the 20th century. In his book, Religion and Science, he wrote, Whatever knowledge is attainable must be attained by scientific methods. And what science cannot discover, mankind cannot know.

And this, uh, this quote certainly ruffles people's feathers a bit. I mean, particular philosophers who might not think of themselves as scientists. Uh, what do you, what do you make of that quote? And uh, do you think his assessment is correct?

[00:00:37] Samir Okasha: Well, I don't think it's a straightforward matter, actually, in part because it's not really entirely clear what the scientific method refers to. I mean, if he means the methods that science currently uses, including the technologies, say, then it seems unlikely that everything that's in principle knowable is knowable via those methods.

Um, so perhaps, for example, you know, some statement about what was going on in some distant, um, distant region of the universe in the distant past. May not be knowable, simply because all the information has been destroyed and we can perhaps surmise the truth of the proposition but not know it for sure.

Um, so one query I would have with that statement is whether the scientific method is really as well defined as Russell is presuming in that quotation. Other people in philosophy and elsewhere have queried the overall sentiment for different reasons. So some have argued that non scientific disciplines produce knowledge, such as our humanistic disciplines, including philosophy.

And others have argued that personal experience can be a source of knowledge and moreover can reveal information that no science can. So in a famous line of argument in philosophy instigated by an author called Thomas Nagel, a number of people have argued that, um, there, there isn't a sort of information that in principle you can only get by having first personal experience, say, such as the knowledge of, um, what some substance tastes like, for example, you know, what French camembert tastes like, for example.

Some people say, look, how could you, how could anyone know that without tasting it? You know, you could have the most detailed scientific analysis of That, you know, the molecular constituents of ripe camembert, but that doesn't tell you what it tastes like. You have to, you have to, um, experience it. So that line of argument has sometimes been used to, to combat Russell's sentiment too.

[00:02:54] Matt Geleta: Yeah, I think both of those are very interesting points. Maybe let's start with the first one on the definition of the scientific method. I agree with you. I do find it very interesting because I feel like Not only is there not consensus, but there actually are potentially two broad camps of thought here, um, that are relevant.

The first, we have Thomas Kuhn's view, which kind of envisions science as progressing through paradigms in which, um, scientists spend most of their time working within. a particular paradigm, and then on occasion, I guess there is a sort of a paradigm shift. And then on the other hand, we have something that's more like what Paul, Karl Popper would put forward, which is, um, you know, it envisions science as progressing by scientists actively working to falsify the, the current theory or the best explanation.

Do you feel that those two, those two views are at tension here?

[00:03:47] Samir Okasha: Yeah, there's certainly a tension between those two views, uh, between the Kuhn view and the Popper view, which are sort of classic rivals in the 20th century, uh, philosophy of science in, in the study of the scientific method. Or what scientific methodology as we sometimes call that discipline. Um, so as you say, then Kun had this view that was emerged really from his studies in the history of astronomy, um, where he was impressed by these periodic revolutions, which involved overturning the whole scientific worldview, uh, which.

And which punctuated the progress, the process of science. And in between, Kuhn argued, you had something called normal science, which was a highly conservative entity, a highly conservative inquiry, which essentially just consists in fleshing out the paradigm one is working within, but not really fundamentally testing it.

So Kuhn was thinking of his, I mean, his famous, most famous example was the Copernican Revolution, when the old Ptolemaic astronomy, which of course was geocentric, put the earth at the center of the solar system, was overthrown, um, by Copernicus, who, with the heliocentric um, model of the, of the solar system that put the, the sun at the, at the center, um.

Now, whether that model of normal science punctuated by scientific revolution and paradigm shift really applies to every scientific discipline in every era is rather more debatable, I think. And there's been a lively discussion about whether Kuhn's ideas extend beyond, uh, the physical sciences, which was their original home.

So many people in the life sciences, for example, have said, no, wait a minute. We don't really recognize that description of the history of science or of how scientific activity works particularly well. So I mean, Kuhn's idea is certainly valuable, but I think, um, not many philosophers of science would take them as the gospel truth anymore, if they ever did.

Um, similarly with Popper. I mean, Popper had some, some powerful ideas, um, but his, his methodology, many of us came to feel in philosophy of science, was, was overly simplistic and not really true to what you see. So as you, as you pointed out, Matt, uh, for Popper, the key idea was that scientists should advance bold, bold conjectures, as Popper put it, stick their neck out and advance some hypothesis or theory, and then spend their time trying to falsify it, trying to refute it, to get experimental evidence to disprove it.

Um, and in part, Popper thought that because he thought that It was impossible to prove the truth of a scientific theory, but it was possible to disprove it. Um, which in a sense is true in a, in a, on a point of logic. Uh, one falsifying observation can disprove a generalization, but no number of positive findings can prove it.

because the generalization is potentially infinite in scope and the data are always finite. Um, however, it's a big jump from that and one that Popper was overly ready to make to say that science is all about trying to disprove one's hypothesis or theory. And I think many Many practicing scientists, although they often ironically cite Popper as one of their, um, influences.

Popper is one of the few philosophers of science to have been extremely influential in the practicing scientific community. But ironically, despite that influence, Very few scientists actually do what Popper said, uh, that they, that they should do, which is try and disprove things rather than to establish them.

So I think the Popper methodology, for different reasons to the Kuhn one, is also, um, untrue to much scientific practice, in my opinion.

[00:07:57] Matt Geleta: Yeah. I mean, it does, it does still feel like there is something intuitively resonant about Bertrand Russell's statement. And I think, um, in, in earlier writing, he also said some things that were sort of a little bit. distasteful towards philosophy, I would say, but even though he was very much a philosopher in his own right.

Um, in fact, you know, through this podcast and through, um, my work with, um, tech startups and other things like that, I have a fortune of speaking with, um, a lot of great scientists, a lot of great philosophers, great technologists. And often when I ask them a difficult question, they might. couch their answer by saying something like, Oh, that's a philosophical question.

And then they'll go on to give me their opinion. Um, and I always actually sort of, it reads to me as a euphemism for this question has no answer or this question has no objective answer. What is your view? Is there a distinction between philosophical questions and scientific questions?

[00:09:00] Samir Okasha: Yeah, it's, that's a good question and an age old one. Um. My opinion is that there is, in that the questions we ask in philosophy are not directly, um, open to, um, demonstration one way or the other. So in philosophy we ask questions like, what is knowledge? Um, what is truth? Is truth attainable? How should humans behave?

How do we reconcile, how should society reconcile the welfare of the group against the rights, with the rights of the individual? Questions of that sort, which are age old questions and, um, are not the sort of question that admit of a final resolution. That you could hope to finally answer in a way that would just settle the matter once and for all.

As with some well posed scientific questions, one can do. Say the question of what the molecular makeup of water is, is not a matter of debate. It's something that, where the truth has simply been established, we know the answer. Um, Or how many miles the moon is from the earth. I mean, these are factual matters to which we know the answer.

Any, if there's any debate on them, then one party is just straightforwardly wrong. But philosophical questions aren't like that. And that's why they never get resolved and have been debated for thousands of years, in fact. So that's, that's one symptom of the difference between a science, between some scientific questions and typical philosophical questions.

Um. But I think that more fundamentally, the difference comes down to the difference between empirical knowledge and what we might call a priori knowledge. So a priori means without the benefit of experience. So the scientific method, as Russell was alluding to in that quotation, is fundamentally empirical.

You know, so, you know, in scientific inquiries, you can't, with a typical scientific inquiry, you can't know Or even have a reasonable belief about something without investigating it empirically, studying how it actually is. Um, so take, I don't know, take the question of whether COVID emerged from a lab leak or from the wet market in, in, in China.

that debate. Now, we still don't really know the answer for sure, but you couldn't possibly address that question without going and looking at the evidence, looking at the empirical data. That's typical of a scientific question. The way to answer it is empirical, where empirical means making observations, doing experiments, finding data.

But standard philosophical questions are not really, um, responsible to empirical data in quite the same way. So come back to the example I gave you a moment ago, the question of what knowledge is. What do we mean when we say that someone knows something? That's one way of posing the question of what knowledge is, a question that goes back to Plato and before.

Now, ask yourself, I mean, what experiments or observations could we possibly do to decide what knowledge is? I mean, we could do a survey of how people use the word, no, I suppose, but that wouldn't quite tell us what we, the answer to the question, although it might in some cases be relevant. Um, and that, that, the lesson here, I think, is that Typical philosophical questions, one can adduce reasons for and against the answers that one might want to give to them, but they're not fundamentally based on empirical information in the way that empirical information is the arbiter of scientific hypotheses and propositions.

So I would say that there is a fundamental difference between science and philosophy. reflected in the fact that the method of inquiry in the two disciplines is really quite different. Now, the mud, the waters get muddied a bit by the existence of the discipline called philosophy of science, which is in fact my own discipline, which is a sub branch of philosophy.

And one of the things we do in philosophy of science is to study sort of Conceptual questions that arise within sciences and also methodological questions that arise in most or all sciences. So we started with the discussion about Kuhn and Popper. Those are examples of methodological questions that arise.

Um. pretty much in all science. Now, I would still classify that sort of inquiry as philosophical, rather than, um, scientific. So, for example, one classic question of scientific methodology is whether experimental data can ever prove that a hypothesis is true.

Now, Some people say, no, no, no, it can't, not, not in the strict sense of the word proof in, in, in that strict sense in which we'll say we can prove Pythagoras theorem by purely, purely mathematical means. Many people say, no, even the most, the most powerful Convincing experimental data can never prove a hypothesis in that sense of the word proof.

But then we get into the question of, well, what, what experimental data can do? How rationally certain we can be about scientific hypotheses and theories, um, given if, if we grant that the data can never prove their truth in the sense in which we can prove a theorem in, in geometry, for example. Um, and that I think is a, is a, is a philosophical question.

I mean, it's a question about science, about how much certainty we can rationally place in the deliverances of science, but nonetheless, that's a philosophical question. It's not to say that only philosophers are equipped to discuss it. On the contrary, many scientists have and will weigh in on that very question too.

But fundamentally, it's a question about rationality, if you like. or about what the rational response to evidence and information is, and about how much, um, support evidence can give to, um, an, an empirical hypothesis. And those are, I would classify as philosophical questions about science rather than scientific questions.

So in short, coming back to your, your question, I do indeed see a fundamental difference between philosophical questions and scientific ones. Now, not, not all philosophers agree with that.

[00:15:59] Matt Geleta: Oh, interesting. Um, I would, I would actually love to dig into that. Uh, for, for what reason do some philosophers not?

[00:16:06] Samir Okasha: Um, a line of argument associated in particularly with the mid 20th century philosopher and logician W. V. O. Quine, Willard Van Orman Quine, maintained that science and philosophy are actually continuous. And that it's a mistake to see a hard and fast divide between them of the sort that I've been arguing for.

Um, and that was essentially because Quine didn't really believe there was a distinction between empirical knowledge of the sort that science gets you and a priori knowledge of the sort that philosophy or mathematical reasoning might get you. He thought that that very contrast didn't make sense. And.

As a result, advocated a position that came in some quarters to be known as naturalism, which holds, roughly speaking, that philosophy and science are on a continuum, if you like. Um, that it's not that there's a hard and fast divide between them. It's just that philosophy asks questions that are further removed from Um, experimental or empirical data, um, but so that, you know, the theoretical reaches of some sciences do that to ask questions that are really at some removed from, from the empirical data.

So according to this, um, quine inspired line of argument, there isn't a fundamental divide between the two. That's what I was thinking of when I said that some philosophers would disagree with what I've said. Absolutely.

[00:17:40] Matt Geleta: Yeah, I guess, I guess if we do take the, the sort of first view you put forward, it does pose a question of how one could make anything that we would call progress in philosophy. Um, because in science you can imagine even if one cannot prove progress. Um, one could at least, you know, disprove, as you said earlier, and sort of cut out the space of possible hypotheses, make it smaller, or at least have enough evidence that it could sort of draw us towards, um, a stronger belief in, in a certain region of hypothesis space, I guess.

And, and I, I would consider, you know, mathematically, you could think of that as, as progress of a sort, but in philosophy, we don't have the ability, then, to appeal to, I don't know. Empirical evidence. So what does, what does progress then look like in philosophy?

[00:18:28] Samir Okasha: It's a good question, and one, I think, that actually troubles a lot of us in philosophy, in that we spend our lives beavering away at these extremely difficult questions, and, um, reading difficult works and writing, in many cases quite abstruse, uh, articles in modern professional philosophy, often that can only be read by other philosophical specialists.

And we would hate to think that, uh, it's wasted effort, that we're getting nowhere. Um, So, but nonetheless, the comparison with scientific progress is unflattering for philosophy in that, as you rightly say, I think, Matt, I mean, whatever one thinks about whether you can prove the ultimate truth of scientific hypotheses.

I mean, it's very hard to dispute that science makes and has made extraordinary progress. Um. So I think it's very hard to dispute that science makes progress. Um, and tech, the technological, um, spin offs of science are, are, are testimonies to that. And of course, the theoretical understanding too. Um, and that, that I think is, is, is agreed by, by pretty much all parties that science has indeed increased the stock of human knowledge and has, as you rightly say, Matt, eliminated certain things that we once believed and given us pretty, pretty good information about all sorts of different things.

Philosophy, however, doesn't seem to have made progress in quite the same way. And indeed, many of the questions that the ancient Greeks discussed in philosophy, in fact, Pretty much most of them are still discussed today. Should we worry about that? Well, I would say no. I would say we have made progress, great progress in philosophy.

It's just that the questions we ask are not of this, not the sort that have final answers. So the progress could never take the form of in philosophy of saying, we now know the answers to these philosophical questions and. we've disproved to the earlier generations. I think the progress takes a perhaps a more subtle form in that the aim of philosophy really is clarity rather than final truth.

Um, so what we're often doing in, in philosophical inquiries is really trying to Shed light on debates that have interested previous generations of philosophers and to pose the questions more sharply, um, and more accurately and in that way to to illuminate, if you like, and I do think that the great advances in the, in the field of philosophy that we call analytic philosophy, that's largely a 20th century endeavor.

So, you know, really only, um, maximum of about a hundred and 130 years old or so, probably less, has indeed brought a lot of clarity. So one of the hallmarks of analytic philosophy is to use logic and careful analysis of language to really ask exactly what the question is. And by doing that, then what analytic disambiguate

many of the questions that earlier generations of philosophers argued about. Not necessarily to achieve any final answers, although perhaps some, but rather just to clarify what the question is in the first place. Now that looks very different from scientific progress, I grant you, but I think it's progress nonetheless.

[00:22:19] Matt Geleta: 1, 1, 1 viewpoint that many people take when thinking about science and, and, and philosophy and scientific and philosophy. Philosophical questions are that many people view scientific questions and, you know, scientific knowledge as purely, um, descriptive. There's, you know, not normative at all. They're no value statements, and I think Bertrand Russell and Thomas Kuhn and Carpa, all the people we've mentioned, their views seem to be.

roughly consistent with this way of thinking. But there is one science that I think breaks the rule here in particular. Um, and that is biology. Um, in biology, there is a lot of value laden language that's, that's used. Um, so for example, if I look at the, the. The human heart. Um, it's very common to say something like, um, the purpose of the heart is to pump blood or the, the, the function of the heart is to pump blood.

And you would never say that about, you know, a chemical reaction doing something. You never say, the purpose of this reaction is to do X, Y, and Z. Um, and so what, what does that mean then for biology as a science? Does that, does that change how we think about this, this type of science?

[00:23:29] Samir Okasha: that's a very nice question. Um, Let me answer it in two parts. Firstly, I agree with the general idea that science... yields knowledge of what the world is like, not what the world should be like.

[00:23:46] Matt Geleta: Hmm.

[00:23:47] Samir Okasha: Um, so there's a fundamental contrast in philosophy that we make between the descriptive and the normative, where the descriptive uses the language of is.

It says, this is the way the world is. The normative uses the language of ought and says, this is the way the world should be in some respect. Now, David Hume, famous 17th century Scottish philosopher, um, sorry, 18th century Scottish philosopher, argued that, um, one could never get from An is to an ought.

That there's a fundamental gap between those, those two things. And my, my own view is that Hume is right. And I think that that's enshrined in, in the scientific world view to some extent. In that we think of the job of the scientist as just being to tell us the facts as best as possible. Um, the question of what one does with all of that scientific information then is a sort of ethical or social or political question to be assessed by, you know, by policymakers in, in part.

So that's the is or divide. Now, you suggest, Matt, that maybe Biology is an exception to that because of the prevalence of functional and purposive language in biology. Let me firstly say I fully agree with you about the presence of functional and purposive language in biology. You gave the example of the heart.

We say that the function of the heart is to pump blood, or the function of the kidneys is to remove waste products from the blood, or the function of the crab skeleton is to, to protect its innards, or the function of the, the bird's mating display is to attract females or, or whatever. So. I agree with you on the face of it, that may sound normative.

We might be saying that, you know, what the heart is meant to do is to pump blood around the body. And, uh, a heart that doesn't do that is defective in some way. And defective is obviously a normative term. We're saying it's not doing what it should do or what it's meant to do. And now one might say, impressed by the is ought distinction, the Hume argument, well, it seems that that violates then the general idea that the job of science is to, um, describe the world rather than prescribe.

But ultimately I think that that's the way it seems rather than really is, in that, Much, um, apparently normative language, in particular purposive language in biology, can in fact be paraphrased away in, in purely descriptive term. And according to one line of argument,

what we really mean when we say that the function of some biological item is to do X rather than Y, what we're really saying is that's why, that's why natural selection

So, you know, if I say that the function of, uh, the salmon's, um, returning to its natal home, its homing behavior, uh, is in order to, um, raise its offspring in, in, in a safe environment or something, then what I'm saying is it's because the behavior, the homing behavior has that effect that natural selection led.

Salmon to do it, if you like. So according to this line of argument, function and purpose, talk of function and purpose in, in biology is ultimately shorthand for talking about evolution by natural selection. And so if I say that the function of the heart is to pump blood, I mean, that's why hearts are there.

That's why they evolved in order because they do that. Whereas it's not true to say that the function of the heart is to make a, make a thumping sound, even though the heart does make a thumping sound. Um, that's not why hearts evolved. That's just a side effect of their true function, which is to circulate the blood.

So according to this line of argument, we can, we can translate away talk of function, um, by paraphrasing.

Functional language or for purpose of language in purely descriptive terms. So in short, if that's right, it suggests that evolutionary biology or biology generally is not in, is not in fact an exception to the rule that science deals in is rather than ought.

[00:28:57] Matt Geleta: I, um, I want to later on get back to the is ought question, um, as it pertains to questions of ethics and morality, but, but I think let's spend some more time on, on this question of function for now. I think there are two things that come to mind here. if, if we are to take the view that what we're really doing when we use value laden language here is pointing towards, you know, evolutionary purpose or, you know, the reasons for things having evolved.

The first idea here is that, you know, for the, for the vast majority of, of Um, you know, uh, written history, um, the theory of evolution was not known and, um, you know, science was still, still done, even in a period where biology was, was thought of as a science. The theory of evolution was, was not understood and functional language.

Functional language was used, and in fact it was used even earlier on in, in other sciences as well. Um, but maybe let's start with, with that. Um, how does that then, um, apply to this, this case where functional language was used, and, and I think we're saying it was used for a purpose that actually was, was not known, um, at some point in history?

[00:30:08] Samir Okasha: Yeah, no, that's that's a fair point. Um, so to take a concrete example of that, I mean, so many, many schoolchildren know that, uh, it was William Harvey who, who discovered that the function of the blood is to, sorry, the function of the heart is to pump, um, is to pump blood around the body. And of course, he was writing many, uh, many, many centuries before Darwin.

In which, so at a time when the theory of evolution was not known and where almost everybody believed instead in, in bi creation. Almost everybody in the, in the, in the Western, uh, Christian world that is, believed in biblical creation. Um, But nonetheless, Harvey was able to discover that the function of the heart is to pump blood.

And so you might say, well, then how can it be plausible to try and analyze away that language in terms of evolution and natural selection, given that he was using that language long before the discovery of the theory? But in response to that, We might say, well, look, we're not really trying to give an analysis of what every person who's used the term function has meant.

Rather, what we're doing is trying to point to the underlying scientific facts that make talk of function sort of scientifically possible or scientifically respectable in biology. So the basic idea would be, well, I mean, functional talk gets a grip in biology, but not in chemistry or geology precisely because the organisms that we find in biology and their, and their sub constituents, their cells and molecules of which they're made, appear to be designed for a purpose.

And now, some people, you know, in the pre Darwinian era, thought that they really had been designed by a conscious designer for a purpose. But what Darwin did is essentially to show that natural selection was the designer. if you like. So there was no intelligent designer, rather the entity organisms came to, um, be like incredibly well designed machines, very well adapted to their environmental conditions because of natural selection.

However, What really vindicates the functional talk is the fact of apparent design, if you like. And the, and the design being merely apparent, which is what Darwin showed us, rather than real, as proponents of a theistic worldview believe, doesn't really matter insofar as our ability to correctly identify the functions of things is.

So that would be, I think, one way of responding to the objection that you point out.

[00:33:12] Matt Geleta: Yeah, yeah, I guess that, that makes sense. So, you know, this, this language happens to be. Um, you know, subjective or value laden in, in other contexts, but in, in this case, um, it makes sense and is appropriate, um, but it does then, um, lead to a second objection. And this actually, I think a very famous objection that was first put forward by, um, Stephen Jay Gould and Richard Lewontin in the 70s, I think, they wrote a very impactful paper, um, arguing that, um, those, I think they call it the adaptationist view, you know, trying to, um, describe traits.

of biological organisms by appealing to their evolutionary origins. Um, they, they claim that this was not really a real science because people would be able to look at basically any trait and come up with a very convincing sounding story, uh, explaining the origin and therefore the purpose of the trait and, you know, this would be the functional language we just talked about.

But, um, you know, these origin stories I think could often not be True, um, or that we would have no means of knowing whether this was the true purpose or origin or, or function of this trait. Um, and this is, I think this is very common today in the field of evolutionary psychology and the, um, the popularizations of, of that.

So, um, how do you think about that objection? Are, are Gould and Lewontin right in this case?

[00:34:41] Samir Okasha: Um, yeah, it's a complex matter. My own view is that Gould and Lewontin... Did have a point, although they overstated it somewhat, but that the correct response to the point is not to abandon what they call the adaptation, um, approach to, to evolutionary biology, but rather to do it better if you like. Um, so as you, as you point out, Matt, then one of their key worries was that, But because of their predilection for using the language of function and purpose, that what many evolutionists within professional biology, um, were doing, according to Gould and Lewontin in this famous 1977 paper, was to simply advance what they call just so stories.

And that was a reference to, to Rudyard Kipling's children, children's books, you know, how the tiger got his stripes, that, that series of books. Um, so according to Gould and Lewontin, then researchers. Was simply deciding ahead of time that every feature or trait, as we say, of every organism had been designed by natural selection for a purpose.

And would they just invent hypotheses about what that purpose or function was, what the benefit it was, uh, that it conferred on organisms was. Uh, without really having a good methodology for determining whether those functional claims are true or not. So, in short, their charge was that people were not behaving as Popper said the good scientists should behave, namely, actually testing, um, a hypothesis.

Rather, they were just assuming ahead of time that, um, every interesting feature of every organism had evolved by natural selection for a specific purpose and then hypothesizing or guessing about what that purpose was but without any good way of telling whether the guess was true. So this was a fairly damning sweeping critique.

that Gould and Luonton made of a mode of reasoning within professional biology, um, a sort of Darwinian inspired mode of reasoning that was in fact probably more prevalent in the UK than in the US where they were making the charge in that in, in, in the UK, there's always been a stronger. commitment to the Darwinian adaptationist, um, paradigm within, within biology, um, and, and in, in the, in the, in the public at large, probably too.

However, what, what's the right response to the points that Gould and Lewontin were making? So let me take one of their, one of their famous examples. They said, look, think of the human chin. Right. I mean, it would be quite wrong, they said, to try and reason as follows. Well, all humans have a chin, therefore the chin must have been produced by natural selection for a purpose.

And so therefore maybe the, the, the function of the chin is X, Y, and Z. Because they pointed out that the chin is just an inevitable by product of the growth of the jaw, just as a, it's a purely anatomical consequence of the way that the jawbone grows. Um, and not all, not all other great apes have chins, so, um, that's what they meant by a spandrel or a side effect.

They said it's just a side effect of the construction of the organism, that it has this feature. And it would be, it would be quite wrong to try and ask a question about what the adaptive advantage of the chin is, there's none. So that's an example of one of their lines of reasoning. But I think the question we have to ask is not whether they had a point, I mean, I think most people agree they did have a point, but what the right way of dealing with that point is.

Um, and I think that the, the, the, The answer to that, in my opinion, is that you need a raw, you need a more robust methodology. You need to be sure you need to make a clear distinction between things that are known pretty much for sure. And things that are still sort of hypothetical guesses. Um, and you need a clear way, established way of testing adaptive hypotheses to try and determine if they're true.

But I think in the, in the, um, the 50 or so years since. Gould and Lewontin wrote that famous article. The situation has changed a lot, and I think evolutionary biology, through a combination of molecular methods, use of molecular information, and more sophisticated statistical methods for testing hypotheses, and more advanced modeling.

efforts by people making, uh, theoretical models of how evolution works have sort of raised their game. And so in my opinion, the Gould and Lewontin critique, um, it doesn't really apply as much as it did once. So I would give a sort of nuanced answer to your question. I think they did have a point and it was a valid point and one that we still need to bear in mind, but it's not fatal to the enterprise of giving adaptive explanations.

[00:40:16] Matt Geleta: Yeah. Yeah, I think it's actually a really important fact actually that you mentioned that we have made a lot of progress in this domain because I think these sorts of stories are often used to justify real world decisions and how people think about the world. One of the, one of the quotes that I remember reading was one from Noam Chomsky and he said something like, you know, you find that people cooperate and then you say, yeah, it's of course, it's because it contributes to their genes perpetuating, um.

Or you say you find that they fight and then you say, yeah, that's obvious because it contributes to their genes perpetuating and not somebody else's. Um, and so this, this goes back to, to that point. Um, but I think, you know, that also if you apply that to a real world situation and you come up with the, the wrong story.

and it's not a scientifically backed story, you could then perhaps, for example, infer that people are just like a particular way and all the things that that could lead to, you know, historically we have, um, uh, things that go as far as eugenics as an example of a, of a consequence of having a wrong view here.

[00:41:21] Samir Okasha: Yeah, I mean, the whole business of the application of evolutionary reasoning to humans is, um, obviously fraught with danger. Um, we have the unfortunate history of eugenics and of the social Darwinism movement to bear in mind and of the rather unfortunate debates about race and IQ in, in the U S particularly, I mean, there's a lot of, um, difficult history that one has to.

Uh, be mindful of if we're, you know, concerned to apply evolutionary reasoning to human behavior, um, or to seek genetic bases of, of complex human behaviors, uh, that, no, that's, that's absolutely right. I mean, I think you're, the example you give from Chomsky is a nice one. I mean, and that's incidentally exactly the sort of thing that Popper had in mind when he insisted on the, the methodology of falsification.

He said, look, it's no good to, you can always find something that confirms or seems to confirm your theory. You know, it. If your theory fits the facts, whatever those facts are, then that's not good. That's bad, right? And as you say, I mean, if we can explain both the human propensity to cooperate and the human propensity to fight in exactly the same way by saying, oh, it's just a matter of spreading your genes, it's basic Darwinian logic, then that is.

problematic. I mean, because, but again, I mean, the response in that case that I would make is to say, well, we need to have a more accurate description of the phenomenon itself before coming up with evolutionary explanations for it. So humans cooperate. Yes. In certain contexts, in certain institutional settings, um, but not in others.

And similarly humans fight. in certain contexts, but you know, a careful anthropological or sociological analysis of that will reveal that it's not just sort of random, if you like. There are significant regularities or generalizations one can make about when humans cooperate and when they don't, and when they fight and when they don't.

Um. And until we have a sort of better description of the pattern of behavior itself, we shouldn't really try and construct evolutionary explanations at all. And of course, in the human case, the evolutionary explanation will only be part of the story because culture plays such a significant a role in determining human behavior, culture, and social institutions, um, that it would be quite wrong to think that there's a very direct connection between um, humans genes and what the natural selection has selected our genes for and our behavior.

I mean, there is at a very broad level of analysis, but at the level at which we're typically interested, then the differences in human behavior are almost certainly more the results of cultural environmental influences than genetic ones.

[00:44:40] Matt Geleta: Yeah, I mean that leads very, very nicely to one of the traits that's really right at the center of human life, um, which are our moral and ethical sensibilities and, um, in particular altruism. Um, I think that, that pertains to the first part of Chomsky's quote. I mean, as, as with, um, other human traits you've talked about, I think you, as you said, the, the scientific consensus is that.

There are aspects of this that have evolutionary roots, and maybe there are cultural influences and so on. But I would like to explore the evolutionary roots then, in light of what we've just talked about. I mean, the evolutionary origin of something like altruism, it's a big topic in itself and could warrant a podcast.

But perhaps we could just briefly set the picture here on our leading theory for evolutionary origins of altruism. Because I think this, this will lead very nicely back to the no altremes point that we talked about earlier on, which I want to get to. Um, so maybe we need to touch on concepts like levels of selection and group selection and kin selection and those things.

But, um, could you quickly set the, the picture for me here on, on this question?

[00:45:46] Samir Okasha: Yeah. I mean, I think first of all, we need to distinguish whether we're talking about humans or non humans because the term altruism, you know, is used in, in biology in one sense and is used in, um, In application to humans in, in both in, in the field of psychology, but also in, in day to day, um, conversation in, um, in a slightly different sense, there's a relation between the senses, but they're different.

So let's firstly talk about the biological sense. So what one means in, in biology when one describes, um, some animal behavior as altruistic is that, It imposes a cost on the, the actor, the organism that does the, the action, but benefits someone else. So, you know, sharing one's limited food supply with other members of the social group, or something, would count as altruism.

An animal that does that gets less food for itself, uh huh, so its own survival is presumably reduced, but it enhances that of, that of someone else. And now... This immediately raises the question of how altruistic behavior, which is relatively, which in that sense is relatively common throughout the animal kingdom, and indeed not just the animal kingdom, we find in, in microbes, in particular in bacteria, remarkably engaging, um, in, in similar sorts of behaviors, behaviors that are individually costly, but that benefit others.

Um, such as releasing certain, producing certain chemicals that will free up, you know, iron for bacterial metabolism into the local environment. But other bacteria will be the beneficiaries, not the, not the bacterium that produces the, uh, the, the chemical in question, which is costly to produce. So altruism of that sort is common, uh, throughout the, the living world.

And immediately that, that raises a puzzle. I mean, from a Darwinian perspective, our natural sort of first expectation is that animals and organisms should evolve behaviors that increase their own chances of surviving and reproducing, not those of others, right? So then how can the existence of altruism be reconciled with basic Darwinian principles?

With the basic Darwinian idea that, you know, there's a competition between individuals and individuals who exhibit behaviors. that bring the most chance of surviving and reproducing will prosper and spread their genes vis a vis ones that behave altruistically, for example. Now this puzzle was indeed fully appreciated by Darwin himself.

Um, both in The Origin of Species and even more so in his 1879 book The Descent of Man. In which, in a famous passage, Darwin posed the quest, the puzzle of altruism by saying, imagining how, um, altruistic behaviors had evolved in early hominids. So Darwin, in particular, was talking about early hominids who were willing to sacrifice themselves for the good of others in their tribe or group.

So, as Darwin famously put it, he said, he who was ready to sacrifice his life. would often leave no offspring to inherit his noble nature. So in saying, with that quotation, Darwin was precisely saying, look, there's a puzzle here. We've got the theory of natural selection, leads us to assume that individuals will look out for themselves.

But then we've got the existence or supposed existence of self sacrificial tendencies in early hominids. How do we square them? Now, there are a number of possibilities. I mean, one possibility, and this is what Darwin hits on himself in that, in that same discussion in The Descent of Man, is that Natural selection may in fact be favorably operating at the group level, not the individual level.

So it might be that in group on group competition, groups containing lots of altruistically inclined Individuals who look out for the common good will prosper over groups containing selfish ones. And so it might be that we need to think of selection between groups, not just between individuals, to understand how altruism evolved.

That's one, that's one theory, sometimes called group selection, also known as multi level selection. Another idea, um, That in some, is related in a way, although came, arrived by a very different route. And, in fact, it wasn't the true relation between this idea that I'm about to expound, and the group selection idea, um, only, only came to be understood relatively recently.

But in any case, this second idea is sometimes called kin selection. And this is associated particularly with authors like W. D. Hamilton, the Oxford biologist. an inspiration for Richard Dawkins, and it's at the heart of much of Dawkins early work, is the idea that we need to think in genetic terms. And the key observation here is that altruistic behavior in the animal world is not usually just directed at random members of the population.

So it's not generally the case that an altruistic organism will Behave altruistically just to anybody, but is rather to their relatives, or to those who are in close proximity to them, who statistically often tend to be their relatives in many animal communities. And that changes the accounting fundamentally, because you see relatives share genes.

So, so long as an organism is behaving altruistically towards fellow altruists, sorry, towards its genetic relatives who share its genes, then it's likely that the benefit of the altruistic behavior will be falling on other people who also have the genetic trait that leads to the altruism. So, in that way, It can be, in fact, a mechanism by which genes that encode altruistic behavior can spread through a population.

So long as they cause the, the organisms in which they're found to be altruistic towards other organisms that also have the gene, or more likely than random to have the gene, to, to be precise, uh, then altruism can spread. So in short, this is the idea of kin selection, which posits that there's a simple way of explaining in natural selection terms how altruism could evolve, simply by appealing to the fact that, um, Organisms typically behave altruistically towards their relatives, not to randomly chosen members of their population.

So that's, that's biological altruism, altruism in the biological domain, where we've got the group selection idea, the kin selection idea, and the fraught history of debate between those that still goes on to some extent, although the situation is much clarified now. Okay, so that's biological altruism. Now, I said, um, a moment ago that when we talk about altruism, we've got to distinguish a bit between the use of the term in biology and, uh, where it's a sort of semi technical term, if you like, to refer to behavior that's individually costly but benefits others. And the use of the term in reference to humans, so many authors have talked about what they call psychological altruism.

And psychological altruism refers to behaviors or actions that are done with the express intention of helping others, that, that are personally costly, but where the aim is to help. others. And that's sort of subtly different from the evolutionary or biological altruism notion, because you see a bacterium that releases some chemical into the local environment obviously isn't consciously trying to help anyone.

Um, it doesn't have a mind. So It would be a nonsense to say that it was trying to help other bacteria in its, in its social group or something. Um, but in the human case, then clearly much, uh, human behavior is not, though not all is done for conscious with conscious intentions underpinning it. And so we can sensibly say, look, did that person perform the action because they were genuinely trying to help or were they just trying to look good in the eyes of someone else?

So when you, you know, when you help that old lady across the road, um, is it cause you really wanted to help her? Or, you just wanted to impress some onlooker and show them you were a nice guy, for whatever reason. So, in the human case, we can make that fundamental distinction between, um, actions in terms of the intent to help versus not.

Um, so we need to, so when we ask whether there's a biological basis for human altruism, we immediately have to say, well, what do we mean by human altruism? You know, do we mean altruism in that psychological sense or do we just mean altruism in the same sense in which we talk about altruism in ants and bacteria, namely doing things that in fact help others but are costly to oneself?

So I think the question of the biological basis for human altruism is complicated by that, by that sort of semantic or conceptual distinction. And it's also complicated by the fact, the general fact that we've alluded to already, that, you know, much complicated, interesting human behavior, um, Is only under very loose genetic control, if any, if you like, in that, I mean, clearly our genes in a way affect our aspects of our mind and our brain and our psychology, but don't directly determine how we behave in a, in a day to day fashion.

I mean, culture is a far stronger determinant of that, I think, in the human case. Um, so wondering whether there's a biological basis for human altruism is, um, is complicated for that reason too, namely that the attempt to, um, find biological bases for human behaviors is typically not particularly successful.

I mean, it's not to say the genes are nothing to do with human behavior at all, but at the level of grain at which one is typically interested, um, specifically, if you, if you look at, if your, if your concern is with differences in human behaviors between people in different parts of the world, for example, genetics are unlikely to be anything to do with it.

[00:57:28] Matt Geleta: Yeah, there, there is that lens though, um, I mean, as, as you say, altruism could have sort of many different layers to it and there, there might be sort of a quote, unquote, purely genetic component, genetic component, um, and then there might be others that are sort of much more nuanced, but at bottom, I think everyone.

It would agree that, um, you know, even the, the, the quality of the human mind, the nature of the human mind, what it can do. At bottom, this is something that has, um, evolved and does have evolutionary origins. And I think this comes. Back very nicely to the ought versus is question that we discussed earlier, because altruism and, um, in fact any other sensibilities we have, um, they are, however many layers we have on top of them, they're somehow at the, at, at bottom.

are determined by the structure and nature of our minds. And, um, you know, we, we said that the, the most standard view, I would almost actually say it's, it's taken as almost like a principle in philosophy that there is, there is no ought derivable from an is. But if you think about it, moral sensibilities, um, are, I mean, they, they emerge from this, this process of evolution and everything on top of it.

And that is a pure, The is process that is a purely descriptive thing that happens. And so all of the ought exists somehow within a, um, a universe of is. And so how do you think about this, uh, this issue?

[00:59:02] Samir Okasha: Yeah, no, that's a nice way, nice way to put it. I mean, I suppose my, my own take on it will be this. I'm not saying this is, uh, sort of established fact in philosophy exactly, but it's, it's how I would look at it myself. So I, I'm a believer in the is ought distinction. I, I agree with the, the principle that you can't get an ought from an is and that science most gives us is.

But it's not to say, that doesn't mean there can't be a science of morality. Because you see, evolutionary explanations of, you know, human morality and human moral psychology and human moral behavior, are really explaining why it is that humans, Behave in a certain way or, or have certain moral beliefs and make moral, are disposed to make the moral judgments that they do.

So why is it that we think that, you know, uh, cheating is, is wrong or dodging tax is wrong or hurting people is wrong or that sort of thing. Those are... I mean, if it's, if it's plausible that we can give evolutionary explanations of why humans typically believe things like that, um, then that still isn't to get an is, an ought from an is.

That's to, that's to use an is theory, a scientific theory in this case, evolutionary theory, to explain another is, which is the fact that humans have the moral beliefs that they do. But what you, what that doesn't show is that the moral beliefs are true or false. And it's that last bit that you can't get from science alone.

And indeed some philosophers would even go so far as to say that there's no, there's no fact of the matter. There's no truth there anyway.

[01:00:57] Matt Geleta: Yeah. I think people who are not maybe as schooled in, um, in this philosophical question, um, I think can maybe take the no ought from is. statement as maybe less sort of logically robust as it potentially is and, and maybe take it into sort of more everyday. Um, because I think what we're saying is, you know, there, you could scientifically show that perhaps You know, the vast majority of humans would share some sort of moral sensibilities and We could say that the reason that that happens does have evolutionary roots and so on and and other things But you could imagine constituting a brain differently such that those sensibilities wouldn't be held and I guess in, in that sense, you know, no altruism makes sense, but there are still truths that almost every single person, um, would, would hold or sort of at least beliefs that almost every single person would hold.

Um, and so is, is, is that consistent with your view here? There's sort of like this abstract theoretical sense in which no altruism holds, but nevertheless, there are views that are consistent across basically all of humanity.

[01:02:07] Samir Okasha: Yeah, I mean, I think that's compatible with what I'm saying. Um. So, although I say, I'm, I'm, I mean, I think if you look at humanity at different times then, I mean, things that are commonplace moral beliefs now were not necessarily, you know, 300 years ago, less, let alone a thousand years ago, you know, if you think of the prevalence of institutions, you know, such as slavery, for example, that is abhorrent to every human being alive now.

almost without exception, um, was, was largely taken for granted for much of human history as just, uh, you know, part of the work, the fabric of the world and in, or if not explicitly justifiable. Um, so, I mean, I do think that there has been, you know, moral change and hopefully what I would call moral progress, although not in the same sense in which we get scientific progress over the course of humanity.

Um, But even if, even if there were some invariant, um, moral beliefs or judgments that all humans at all times have been disposed to make and that were sort of deeply rooted in, um, in the, in, in the way that the human brain works or something, and there was a convincing evolutionary explanation of that, I would still be inclined to say that that still isn't getting an ought from an is exactly.

Um, because you see people, I mean people who practice the discipline of ethics or moral philosophy, which is, you know, a sub branch of, of, of contemporary philosophy, they're not always, but generally they are not too impressed with the idea that evolution is going to help them in their, It's not that they deny the truth of evolution or that they deny that evolutionary explanations of human moral, um, judgments and moral behaviors and moral psychology is possible.

But they just say that doesn't answer the question that interests them. Whereas the question that interests them is what is right? What is wrong? What should we do? How should people behave? How should society regulate itself in certain respects? And they say no science can... can tell us the answer to that.

Most of the science could tell us why people think that the answer to the quest to those questions is x rather than y. But they want to know whether the answer is x rather than y. And they typically believe that philosophical reflection is the only way to, Um, and so that's why they, they without, while not disputing evolution, I think many of my colleagues in the, in the field of ethics are unpersuaded that their, um, inquiries, you know, need to really attend to evolutionary matters.

I mean, they may be wrong, of course, but that's, uh, that's what a lot of professional ethicists or moral philosophers believe.

[01:05:20] Matt Geleta: Yeah, it's, um, it does though, bring us back right to the beginning of this conversation where we talked about progress in philosophy and science and what constitutes a philosophical question versus scientific one. And perhaps it's a, it's a conversation for another day, but if, if those people do believe that these questions are in the realm of philosophy, then I think we need to revisit the discussion we had at the beginning about progress in philosophy and answering.

Philosophical questions.

[01:05:50] Samir Okasha: Yeah, no, that's right. I mean, it does lead us right back to, to that Vex question of whether there's progress in philosophy and whether the philosophical method can float free, or philosophical inquiry, let's say, can, can float free of scientific inquiry or not. I mean, there's a sort of growing minority of people in, in philosophy who is, um, uh, who subscribe to what's called naturalism that I mentioned earlier, um, which they, they often take to be the view that, you know, in order to make advances in philosophy, you have to attend to what the sciences say.

And although I myself am a philosopher of science and love science, I, I, I'm neutral on that question in that I think that in reality, many philosophical inquiries, particularly in fields such as ethics and metaphysics, um, and epistemology, Although it's useful to, and, and instructive to bring those discussions into contact with science, ultimately many of the questions that are discussed in those disciplines are questions to which no scientific information is ul is really relevant.

[01:07:02] Matt Geleta: Yeah, well, uh, Samira, I know our time is short, so, um, maybe let's bring our listeners towards, uh, your books and, and what you're working on. Um, you've written several very interesting books on these topics and others. Um, if people want to, to find out more, dig deep into these topics, where would you send them?

Where should they look?

[01:07:21] Samir Okasha: I've written two, two books in the Oxford University Press very short introduction series, um, that I, I, I think might be relevant to, to, to readers, depending on how much they, they know about these topics. So one of those is called Philosophy of Science, a very short introduction, and the other is called Philosophy of Biology.

a very short introduction. And they give a sort of synoptic overview of these two subdisciplines of philosophy, which is where I've done most of my work. That's the first subdiscipline being philosophy of science. And the second subdiscipline being, you know, a subset of philosophy of science. That's the philosophy of biology, which addresses sort of conceptual questions within the modern biosciences.

So these discussions that we've been having about function and altruism and Adaptationism and Gould and Lewontin. They're all covered in that little book. But the first book, by contrast, the Philosophy of Science one, deals with the Kuhn versus Popper issues that we talked about, the question of the scientific method, how much certainty we can have in the results of science, general questions in the field that pertain to all of scientific inquiry rather than to one discipline in particular.

So yeah, if you haven't read those ones, I would, uh, encourage, uh, readers to. Although I should say they're, I mean, they're, they're, they're short books and are relatively introductory. Um, but they are written in a way that I hope makes them accessible to anyone, irrespective of how much philosophy they know.

In that unlike many philosophy books, what I tried to do when I wrote those is to sort of minimize philosophical jargon and just write in as plain spoken a manner as possible.

[01:09:07] Matt Geleta: Yeah. And in general, it's a very nice book series. I remember, um, at Christchurch College in the library, they had the, what looked like the entire, uh, selection of them all across the shelf there, and so I got to delight myself. So definitely worth a read. Um, on the topic of books, um, Which book have you most gifted to other people and why?

[01:09:29] Samir Okasha: Which book have I most gifted to other people and why? Well, I've given Richard Dawkins The Selfish Gene to many, many people, I must say. Uh,

[01:09:39] Matt Geleta: I thought, I thought you were saying that you had given Richard Dawkins a copy of The Selfish

[01:09:43] Samir Okasha: his book, The Selfish Gene, I've, I've, I've given as Christmas gifts. gifts to many people over the years, um, although it's, I mean, it's, it's extremely well known book by now and it's, it's lessons have largely been assimilated. I, I think by many people, you know, who, by many sort of academic writers and with an interest in.

in evolutionary biology. I still think it's an extremely powerful and compelling message, not one that I would say people should swallow wholesale uncritically, but I still can think of no more, no better written, more instinct, instantly interesting and arresting popular science work than that one. mean, Richard Dawkins is not a big fan of philosophy. Um, but like, but I am a big fan of, of, of his work.

[01:10:38] Matt Geleta: Mm. Likewise. Um, uh, next question is, what advice would you give to somebody who wanted to succeed in your field?

[01:10:49] Samir Okasha: I mean, the key in philosophy of science is really. The integration of the science and the philosophy, I mean, so you have to know a lot of science, but you also have to have a philosophical sensibility, and neither of those on its own is really enough. And so, I mean, many people come into philosophy of science via, because they started out, you know, studying science, but they always felt that, you know, standard sort of science curricula, particularly laboratory heavy sciences, just didn't really scratch the itch that, you know, that they had, that they always were, you know, asking some question that the teacher didn't really want.

to answer like questions. What does it really all mean? How do you know that's true for sure? That sort of thing. And so I think that that can often be a symptom that someone is attracted to philosophy of science, uh, but it's not the only way into the subject. So in practical terms, I would say that, I mean, philosophy of science is a difficult subject to get into because you have to You basically have to, you know, have a PhD in philosophy, but also many people will have a, you know, a training sometimes up to PhD level in science too.

And that's a lot of studying. And that requires a lot of funding, unfortunately. So it's not, it's not always the most accessible discipline, academic discipline to enter simply because the sort of knowledge barrier to getting into it. is really quite high and has increased over time. So I would say the key in part is self study.

You know, no one's an expert in anything, but in philosophy of science, we do have to try and be experts in the bit of science we're interested in, though obviously not the whole of science. And also in, in, in philosophy itself. And there's not really any shortcut. So, you know, working hard and self study I think is, is the key.

[01:12:54] Matt Geleta: It's a good, uh, it's a good bit of advice. Um, my final question, perhaps a little bit off topic, but, um, I think very relevant for the times we live in. My question is, imagine looking forward to the day, which many people think is coming very soon, in which we're visited by an AI super intelligence. My question to you is, who from humanity, either past or present, should represent us to this super intelligent other?

[01:13:25] Samir Okasha: Oh, that's a difficult one. I mean, you mentioned Bertrand Russell. I think he would have a case. Nelson Mandela, maybe?

[01:13:33] Matt Geleta: good answers. You can't go, you can't go wrong with Nelson Mandela for sure. Um, uh, Samir, thank you so much for joining me. It's been a pleasure speaking with you.

[01:13:40] Samir Okasha: Not at all. Thank you, Matt.

Paradigm
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Conversations with the world's deepest thinkers in philosophy, science, and technology. A global top 10% podcast by Matt Geleta.