In Our Time - Aristotle's Biology

Episode Date: February 7, 2019

Melvyn Bragg and guests discuss the remarkable achievement of Aristotle (384-322BC) in the realm of biological investigation, for which he has been called the originator of the scientific study of life. Known mainly as a philosopher and the tutor for Alexander the Great, who reportedly sent him animal specimens from his conquests, Aristotle examined a wide range of life forms while by the Sea of Marmara and then on the island of Lesbos. Some ideas, such as the the spontaneous generation of flies, did not survive later scrutiny, yet his influence was extraordinary and his work was unequalled until the early modern period.The image above is of the egg and embryo of a dogfish, one of the animals Aristotle described accurately as he recorded their development.WithArmand Leroi Professor of Evolutionary Development Biology at Imperial College LondonMyrto Hatzimichali Lecturer in Classics at the University of CambridgeAndSophia Connell Lecturer in Philosophy at Birkbeck, University of LondonProducer: Simon Tillotson

BBC Sounds, music, radio, podcasts. Thanks for downloading this episode of In Our Time. There's a reading list to go with it on our website, and you can get news about our programs if you follow us on Twitter at BBC In Our Time. I hope you enjoy the programs. Hello, Aristotle 384 to 322BC was not only a philosopher, but also a great biologist, studying life to help explain the goal of life. As well as the purpose of life, you wanted to know what living things were made from

and where the information came from that made them that way, and he wanted to know what caused them to be alive. While other Greek philosophers only thought of such things, Aristotle was the one who got down on his hands and knees and he examined real life scientifically, from squid stomachs to fish gills to chick embryos, and he developed ideas that were influential for 2,000 years and are arguably still today.

With me to discuss Aristotle's biology are Amun Loha, Professor of Evolutionary in Development Biology at Imperial College London, Myoto Hatsima Carly, lecturer in classics at the University of Cambridge, and Sophia Connell, lecturer in philosophy at Birkbeck University of London. Amon-Larwa. How did he, as a philosopher in Athens, become a hands-on biologist? We don't really know.

And the reason for that is because we don't have Aristotle's diary. All we have are these works magnificent and exhaustive in their scope. and yet which seemed to spring out of nowhere. But we do know something about his life. We know that at the age of 17, he leaves his parental home, which is at the Macedonian court in the interior, and he goes to Athens, where he's a student at Plato's Academy. And he stays at the Academy for many years,

imbibing at Plato's wisdom, and then later on teaching. And then in early middle age, he leaves, and he goes east. He goes to a place called Assos in the eastern Aegean, which is now on the Turkish coast. He leaves following the death of Plato. He leaves following the death of Plato.

And there's some speculation as to why he leaves. So some people have supposed that the reason he leaves is because he was the smartest thing around and should have become the head of the academy. But he doesn't. Plato's nephew, Spusippus, gets the job, and it's possible

that Aristotle impeachians. sort of leaves and joins another group of philosophers who are at in a city-state on the other side of the Aegean. And he's also a foreigner, so he didn't fit in quite as a need later. And indeed he's a foreigner, which is, of course, the more prosaic explanation why he couldn't actually take over the academy. Well, he might have just wanted to push off. We don't know. We don't know. That's right. In any event, he leaves. And somewhere around the time that he leaves, most scholars believe he begins to make this transition from a philosopher in the Platonic morning. to something really very, very different,

something that looks much more like a modern scientist. How would you more further define in the platonic mode? Oh, that's relatively easy. We have Plato's dialogues beautiful and complete, but entirely concerned with metaphysical and moral issues and a philosophy that I would say, but then again I am a scientist, is embedded and founded upon a common.

contempt for the empirical world, indeed for anything that we could call science today. In many ways, I regard Plato as the antithesis of a scientist. And the paradox for me is that Aristotle somehow manages to shake off the influence of this gigantic figure, this penetrating intellect, and reshape himself. He gets to Lesbos and there's a lagoon. Why are those two things significant? Aristotle does biology. begins to do it empirically. I mean, to be sure, he gathers all the information he can. He's an

encyclopedist. But he begins to cut things up. He begins to look at animals. And for that, you need a place to go. Like Darwin needed the Galapagos. Aristotle needed a place. And it turns out that there's this lagoon in Lesvos, this wonderful body of water which bisects this island. And it's one of the richest places in the Aegean. And many of the places that he describes, they're in and around this lagoon and the creatures that he describes. They can be founded them. Thank you. Sophia, let's try to look at the work he did. Well, you're going to. Let's start with matter and form. Why is it useful to start with those two words? Okay, well, you've already heard that he studied with Plato and Plato was famous for having a theory of

forms, but the forms for Plato were separate from the material world and that was very important for them to be immaterial and eternal and understandable, knowable. What would Plato mean by forms? He would mean universals, but they have an existence of their own. Now, the amazing thing that Aristotle did was to put the forms in the world around us. He put them into matter. So the things we see around us are hyalomorphic. They are composed of both matter and form. So when we look at this chair, it has the formed chair and it's made out of wood. So it's a wooden chair and he applies the same reasoning to living beings. So they have a form and they have matter. But this is together. So the animals have forms which are here around us in the world so we can

study them because they're close at hand and we can get to know the form. But the form and the matter in an animal is a bit more complicated than the chair because the form is the way of life of that animal, what kind of animal it is. And the materials are much more complicated as well because they're not just things like wood. If you cut up wood, it will look the same throughout. But there are parts of the body that are like this in animals that he calls a uniform parts, things like bone and flesh. But there are also more complicated parts like organs of the body and parts of the body like hands and eyes, which he calls instrumental parts. And in fact, he says the entire body of an animal or a living being is the matter for that animal. And so you get a much more complicated picture of

matter and form. And so how does it develop that? We have the chair, which is matter and form. We have the animal, which is matter and form. How do you use that to proceed in his method? So one important thing is that he keeps with Plato the thought that in order to understand anything, we need to know its form. And so he's investigating the world in order to find out about these forms that are living around us, these animals with forms such as cat or elephant or horse. And we can come to understand them by investigating them in the world around us. He sees that a cat is a cat, but is he looking at a cat to find out the form? Because he thinks that the peculiarity, a singularity of a cat will add to his knowledge in a

particular way. So each particular animal has a form, which is also its soul, will get on to that. But he wants to know generally what cats will do. And he has a fixity of kinds in the world. So there are cats and elephants and people. He doesn't have a theory of evolution. So he's interested in these because he thinks these forms are eternal. Is that part of his idea of the purpose of life?

Form is attached to his idea of ends. So when we say purpose in life, I think we're talking about teleology. And teleology is his view that in order to have an explanation, we must be aiming towards the end or the telos in Greek. So every animal is trying in itself to live the best kind of life it can for that particular kind. So that the cat is aiming to live the best life for a cat. Each particular animal is trying to live out the good life for that animal,

the very specific kind of life that elephant leads or a cat leads or horse leads. Thank you. Mito Hachemakarly. He's seen as perhaps the first biologist, and in the notes of the three of you you speak very highly of him as the first scientist, first biologist, just let's clear that up. Did he have any sort of predecessors, pre-Socratics and people like that? Right, so there was quite a bit of interest before him in the phenomenon of life. A lot of it was sort of in a medical context, so people would be examining things like reproduction or diseases or things like that from that point of view.

There was a bit of interest in sort of where animals came from and all that sort of thing among the pre-Socratics and the Hippocratic doctors. But definitely there was no one who put all this data together in one goal, let's say, and try to sort of try to find out what do all animals have in common. What do these specific subgroups of animals have in common, kind of laid out there and do what he says. You know, it's a very important thing in his scientific method to first establish the facts. And nowadays, I suppose science, most of modern science is all about, focuses much more on this, how do we establish the facts properly?

But he very much wanted to go beyond that and ask the why. And very often, as Sophia was saying, the why answer is going to be for this purpose. So there were all these predecessors in place. He accuses them of having failed to ask that question of what is this for and having failed to investigate purposes and ends. And there was also, in terms of predecessors, I suppose, suppose there was also quite a lot of specialist knowledge around. So he speaks of having gotten information from beekeepers, from sort of fishermen or earlier authors like that. But again,

he's very keen to point out their mistakes always. And it's very interesting that he says, for example, some fishermen make X mistake because they did not observe for the sake of knowledge. So that's very important to him that he looks at the animals, he does all the investigations, he does, and that is very much for the sake of knowledge and not for kind of some utilitarian purpose. I think we should make it clear to listeners

that he isn't just idling by a lagoon in Lesbos. I mean, he read several books, some mighty tomes which go through the centuries. This is a huge project that he takes on after leaving the academy. How will you characterize his scientific method? Did he have what we could call the scientific method? Again, I can be corrected in this

in how much I understand what we mean by scientific method, but I think ours is a lot about making sure that we have the right facts and sort of double-checking and experimenting and so forth. He, I mean, he speaks a lot about how should we go about this. Like he asks himself, what is the right method to proceed in a biological science. But it's more the sort of questions he wonders about are should we investigate each animal one by one or should we look at what's in common among animals.

So he concludes in favor of the latter. And then really, I mean, for him, definitely the most important thing is that the scientist in order to have any kind of knowledge and count as a scientist has to answer questions why, has to pose them and answer them. That's how you become a scientist and you achieve knowledge properly. Can we develop this, Amo? Can we develop this into, his method, as I understand, it was written down. There were four causes. There were four. He did very systematic in that sense.

Can you give the list of some idea of the systems he set up, which were new in his work? Aristotle does have a scientific method, which Mito certainly captured the core of it. and it's laid out in some very, very dense books called The Analytics, the posterior analytics per se. The other of his analytic books is the foundation of logic. And this is an exercise in logical analysis about how, given the facts,

that you've got in front of you, to make strong causal inferences. So he has a very explicit method to do this. And it's absolutely a scientific method. And it's one that is aimed at very much what we modern scientists attempt to do. That is to say, we take facts, we do experiments. Aristotle doesn't do experiments where we take facts. We do make observations. And we seek to establish causal claims.

So he begins by accumulating all the information he can. He does this in a book called Historia Anamalium. That's its Latin title, The Natural History of Animals. And it's a database, essentially, in which he has all the facts and arranges them in a way suitable for further analysis. And then, as you said, he has a series of eight to nine, depends how you count them, other works in which he seeks to explain the facts that he's put together,

the observations that he's made. And underpinning those causal explanations is this inferential machine that he's invented. And it's not quite like ours, but it does bear historical resemblance. it has the core of much of what we do. It differs from ours in a variety of ways. One way, for instance, is that many of our inferential claims and models

are based upon quantitative data. We do have mathematical models, and we have numbers with which to test them. Aristotle doesn't do numbers. His inferential system is entirely based upon a syllogistic, a set of logical propositions. And you can see this at work in his scientific works, that logical analysis taking its way as he works his way through the arguments on things such as how bees reproduce the way that they do.

It's an exercise and deductive analysis. Thank you, Sophie. What I'm trying to get out is he does establish a series of methods of doing things. You will find out about this. First of all, that, secondly, that, then that. Could you give us one or two examples of this, please? Often he'll start by observing one particular animal, but then he'll infer that what he's found out about that particular animal

will apply to other animals as well. So a good example of this is when he takes apart hen eggs, he sees the development of the embryo chick. This is in the Historia Anamilium. He says, I only have to do hens because this will apply to all birds. It'll be exactly the same. So I can find out generally what's going on here and I can apply it to all birds.

It's just that some birds gestate more quickly, so this process will be quicker and some longer, so the process will be longer. But then in the generation of animals, he doesn't end up sort of dissecting pregnant animal, you know, viviparous or live-bearing animals. He applies the hen information to them as well. And he even talks about the ambilical cord and says it works like this in the egg, but it's exactly the same in a live-bearing animal. Had that been done before, anything like that had been done before that you know about?

Not recorded anyway So he is possibly talking to people who've done it Or he's doing it himself We're a combination of the two Where he has a research team We're all doing this together But there are other things that he infers as well When he's when he's

So he's got to have He's looking for something as well So one of the things he's looking for Is the kind of series of development He's looking at which parts come first And he sees the heart first And this is really important, because for Aristotle, the heart is the center of everything. It's where all sensation takes place.

It's where nutrition is centered and it's creating blood that then feeds all of the body and neutrophies it. And for him, when something has a heart that starts beating, it's now alive. And the end of life is when the heart ceases. So the heart is central to it. Does he also think the heart is the center of intelligence? He thinks the heart is the center of all cognitive activity as well. So actually, but he says in the generation of animals, he says, it's because I saw it.

It was evident to my senses. I saw it. And then I saw the blood vessels coming out. So this is the first, this is the most important part of the body. But then he also needs to explain the development of all the other parts, which he sees as the first parts that you see are the most important parts. So those are the parts that come to be first, the most honorable, the most important parts, and then the other parts are peripheral, less important. They come to be a bit

later. And this is epigenetics. So he's saying, rather than preformationism, which is the embryo just grows, he's explaining how it develops, how it comes to be gradually. Myrto, can we develop something you touched on in your first answer, which is about him gathering information from others, shepherds about sheep, beekeepers, about bees, and so on. Can you give us some more examples of that? And what value he put on that evidence? Maybe you can give us even examples of the value you put on that evidence. Well, I mean, not a great value, I would say.

And it would depend a lot whether or not this information chimed with what sort of ideas he had sort of previously. So there was that example with a fisherman who failed to observe that certain fish do copulate precisely because they weren't looking in the problem. way. Other times, another example is shepherds have noticed that if the animals copulate while facing

north, it's more likely to produce a male. That's very old, I mean, but he reports that. And that sort of... Did he endorse that? Yes. And this is the other way around. Anyway, that it makes a difference as to the sex of the offspring, which,

whether they're facing north or south, it's good to do with temperature. So if you're facing one way and the sort of the bodies become more heated, then, you know, a male is more likely, that sort of thing. And because... Is that true? I have no idea. No.

And I'm sure it's not. But because he has such strong ideas about how much difference temperature makes for the sex of the offspring, he's quite happy to endorse that kind of thing, precisely because it kind of works with what he already thinks. It's worth remembering just observing it getting at this stage, that he had no microscopes, he had no access to. of the technology, which is in every university at the moment. And so this was outside observation the entire time and then thinking. That's right. That's right.

And again, the kind of dissections he had available to him may have been quite limited. And as far as humans, for example, probably he knew only from aborted embryos. Much later, we know Hellenistic doctors performed dissections, even some sources. say even vivisections on humans sort of convicts and so yeah but I still had no idea about that sort of thing so other

other cases where he sort of fault his predecessor I just want to say on this because we you know Sophia was also talking about this that they fail to realize sort of the precise relationship between matter and form so one of the predecessors thought that

humans have humans are more intelligent because they have a very versatile hand like literally our hands can do so many things whereas Aristotle was saying that because humans are so intelligent and their form is what it is that's why the hand is appropriate

to that greater intelligence so it's the same data but other way around explanations for him Amon you wanted to go in I just wanted to say the thing we have to remember member is that he's coming to the organic world, the world of living things, are fresh, right? Nobody before him has actually accumulated information about them. Yeah, there are some doctors and so forth, quasi-quacks. Some of them are perhaps not so bad, the hypocratics, but, and there'll be

some natural philosophers who are sitting around speculating about the natural world and about our animals' work. But he's the first person to actually sort of just attempt to grasp this immense diversity and its totality and he's hoovering up all the information that he can possibly get from anywhere and he's trying to sort it out you know so he's continually evaluating what he hears is it plausible is it not he you know he investigates herodotus herodotus has all sorts of things you know he's talking about firing serpents and then he's pretty severe on herodotus for all the nonsense that he's talking but sometimes he says yeah well that kind of makes sense and so on and so on and he's pulling this all together and trying to turn it into philosophy or science

So let's talk about Aristotle's notion of the soul, the Plato's notion of the soul we know about, but let's talk about Aristotle's notion and why it's germane to this discussion of biology. Absolutely. As Sophia said, the soul is one of the most central notions to Aristotle's theory of life.

And it's an unfortunate in a way that we use that word, Suke, psyche, because we come from the Judeo-Christian tradition, and so inevitably we attach the word all sorts of ideas, Judeo-Christian ideas, especially immortality to the word soul. So that's nothing to do with his idea of soul?

And that's got nothing to do with that. It's not immortal. Not invisible, not good only wise. Exactly. For Aristotle, the soul, and he devotes a whole book to this, and actually it ramifies through practically all of his work, it's the best way to describe it is that it is the system of interrelated parts that keep an animal alive.

Something like that. It is immaterial. It develops when a creature develops in the womb or in an egg, when a chick develops, and when it dies, it soul dissolves. Sophia. Yes, so soul, the work that Armand referred to is called De Anima, and some people think it is actually part of Aristotle's biological works.

So certainly the Arab thinkers put the De Anima before the generation of animals and parts of animals and so on. So it is really crucial that we understand the soul while we are studying living beings around us. As I said at the beginning, the soul is also the form of the animals. So it's all of these interrelated capacities that Armand was talking about. And we can see this in nutrition. temperature regulation, perception, all kinds of cognition, and these sort of set of faculties in every animal. And its body is going to be suited to the soul

because each animal is going to be different. And so he says, transmigration of souls is rubbish because you couldn't make your way into a duck body because you don't have a duck soul. So it isn't, can you, Mirta, to continue this soul, lie. It isn't something that is independent of itself and floats away later. It is the totality somehow combining and the totality

is the soul. It is a bit of a nuisance as has been said that he used their words, isn't it? For us, for us limping along. Maybe it depends, yes, what kind of influences we carry already sort of with us as baggage. But the point is that for Aristotle, it is this set of capacities and it is because we also said that

it's the form of the animal. So it is what makes the animal what it is. So what the animal is, is the set of things that it can do. So if you are just a sort of stationary oyster, for example, you just have life. Or if you're a plant, you're just alive but have no locomotion. So one step ahead for sort of animal, they have locomotive. they are alive so they can sort of nourish and reproduce themselves

and locomotion and sense perception. So that's one step ahead. Human beings, even higher, I mean, this is a evaluative sort of hierarchy there. Human beings are a further step ahead in that they also have intellect, yet another capacity of soul. So all of these things taken together are what make the animal what it is. And that's very important for him.

These decisions obtain between men and women as well? No, I mean, he's very clear when he's talking about human beings that women also possess intellect. There's no question, and that sort of differentiates them from other animals, male or female. Where we find some, the sort of remarks that those of us who really like Aristotle are sort of quite embarrassed by and quite unhappy about is in his other works, the politics.

And that's where he's, I mean, he does say that by nature, women are inferior to men. And sort of, again, the intellect of women somehow has the capacity to deliberate and make decisions, unlike slaves. That's another chapter. Again, that's quite embarrassing. But is not as authoritative as that of males. So women do have these intellectual capacities and he thinks it's natural that they're inferior to men

but that could be sort of him calling natural something that's developed and something that he sees happening everywhere always or for the most part. Social is more than biological. But he would be very happy to call that natural because it occurs everywhere. Well there is a bit of a strain in Aristotle's biological thinking

to have a tendency to talk about women as being deformed, a little bit monstrous, somewhat mutilated. And exactly what he's getting at there and the justification of it, I'd be quite interested to hear Sophia on because she is the expert on Aristotle's theory of generation. So, in a way, the soul of a female animal is not as able as the soul of a male animal. and this really comes down to its nutrigenerative functioning. So what happens in generation is that both the male and the female contributes something to generation,

but the female contributes the materials and the male contributes something like the moving principle, which comes in and makes the change happen so that an offspring eventually comes to be. And if we could think about, lots of people have talked about how the male contributes, the form and the female the matter, but this is a bit simplified. If we think about it in terms of potential and actual, this is easier to understand. So the male contributes the active potential

and the female contributes the passive potential and together they actualize an offspring. So Aristotle thinks that because the female has this passive role, it's not as good as the male. It's always better to be active than passive. And the male also doesn't contribute any material so he doesn't have to get his hands dirty. He doesn't have to do that. And that's better in that superior. So the soul of the female can't quite start an embryo. It can start off an egg so it can do a bit, but it can't get to the embryo and it needs the male in order to do this. So the male is superior. And he has ideas about why there should be a male or a female that comes as a result of this, doesn't he? So I think Mertre referred to this with the agricultural example of the

the wind, that you get a male embryo when the situation at conception is a bit warmer, basically. So the colder conditions produce a female and the warmer conditions are male. And he hasn't got a lot of mechanisms to work with. Heat and cold are something that he uses ubiquitously to explain all kinds of things. So he uses this mechanism in this case to differentiate male and female, also because heat is better. He does stronger. So he's associating, he thinks that males are hotter and they can do more. There's more active power in being hotter.

I was actually, I wanted to invite Sophia to say a little bit more what she thinks about those politics passages, which, I mean, they puzzle me quite a bit as to what sort of connection should we be making between the fact that he does say that women are inferior by nature, this kind of by nature thing. He says that though in the politics. He doesn't say anything of the kind in the biological work. in terms of the intellectual capacities, I mean. So I think biology has released him from that kind of distinction?

I'm really not sure what is going on, and whether or not we really should be looking for a connection. Because I know people are now trying to sort of go in that direction and are trying to see to what extent his biological works are having an effect, are behind what he says in the politics. And I personally, I'm not sure. Well, he makes no explicit connections, as you've made clear. And I think it's really, you have to be very cautious about making these connections for yourself.

The one thing that we do know is that women are colder than men by nature. But this shouldn't affect their intellect, because in fact, in the parts of animals, he says, slightly colder animals have thinner blood and they can think better. So you'd almost think that women might be slightly more intelligent. I think what's going on is about complementarity in the politics. So he wants to find that there are virtues of men, virtues of women, virtues of other roles that people play in the household, and that these will differ. And that in order for the city to work, you need these different roles and the women are playing this inferior role in the city. I think it's time to remember how limited it was by lack of technology, if we use that word, instruments, microscopes and so on and so forth. For instance, he thought, that flies generated, self-generating fly, for instance. But did he doubt that when he said it, or did he say that with authority?

With quite a bit of authority, but I think it was precisely because he didn't have the means to observe that there were probably tiny eggs sort of left by the flies and so forth. So this phenomenon, which we call spontaneous generation, he talks mostly about it in the context of oysters and see sort of animals in shells. They're the ones that their spontaneous generation is the one that he discusses to the greater

with the greatest length. And there, I mean, it's quite an interesting theory in that he says that everywhere in nature, in even sort of the natural heat in the air, there's a little bit of that sort of form or soul that can potentially sort of create a generation. And because those kinds of animals are so sort of low grade, they don't need particularly complicated soul movements in order to generate.

So they can sort of just generate out of the natural heat of the air. Amon? I think there's a real mystery behind Aristotle's love for spontaneous generation. So basically, when he can't actually observe something copulating and giving birth, to creatures laying eggs because the larvae are too small or because of some other quirk of biology, he has a tendency to sort of say, yeah, I think it's spontaneously generated. And the reason that this is so odd is because it's so at variance with all the rest of his biology. I mean, his whole theory, as Sophia said, is that there's a form and this form is embodied in the parents and the parents

transmitted, especially the father via the seminal fluid from father to offspring in the the matter and all that stuff and he's got an incredibly elaborate theory to explain how all that works and then when he comes to when he comes to snails he sort of says well you know form it's just kind of everywhere and you know and and and although you're right he does he does usually do that for the the lower things lower things but he knows perfectly by how complicated snail is we have his dissection of it right he knows it's got organs and stuff and he does it for eels too and he knows that an eel is as complicated as any fish but he says yeah we don't know why come from and indeed it doesn't they've got a very complicated

lifestyle that goes out to the sargassos sea we don't have to get into all that but you know oh I just wanted to add that I think that he really struggles with spontaneous generation that he he devotes a chapter to it in the generation of animals and he's not satisfied he

tries to fit it into his formula of the causes that should be here and he says but they're not here and I think he's dissatisfied I'd say he's dissatisfied with his explanation I just want to address a very interesting thing about snails. He says that snails have been observed to copulate. Very strange, that is.

And maybe it was just recreational sex. And that's not how their reproduction things play. They lay these things that look like egg cases. And some people say they are egg cases. And you can see the baby snails on them. But actually, they're not. No, really. Actually, they're just generated for mud.

But I remember when I first read Aristotle, I remember opening up reading us and saying, those are egg snail cases. I mean, they are. He does think that some animals that reproduce both spontaneously and sexually. I know. It's all complicated and vague and problematic. But he is pretty early on. And you're treating him as if he were one of you and saying,

look, he didn't get this right, didn't get that right. He was two and a half thousand years ago. And as we kept saying, did he work mostly alone or did he learn, a lot of thinking and few instruments and so on? Do you think that even so he could be called in your terms of science? scientists appear? So I don't think he would be called a scientist in our terms, only because he didn't separate off biology or natural science from philosophy, from ontology, from ethics.

So it's quite a modern, the modern world fragments into different disciplines. And for Aristotle, one of the most important things about studying animals is to find these forms to know about the truths of the world and to know about the fundamental realities. These forms and these animals are embodying these forms are what really exist. He calls animals

and plants substances which is his word for what is really important, really exists in the world. Animals and plants are substances more than anything else. So they're the most important things that we should study down here. Not talking about. He also is interested in astronomy, but

we've got the animals right here close to us. So he wants to know about them. So that's, I mean, but on the other hand, I agree with Armand that he has a system, he gathers data, and he comes up with patterns. And so he's explaining things in the way that scientists do today as well. I'm all here. Sorry, not due. I just want to say because we are trying to sort of distinguish Aristotle, the scientist. I mean, the way he sees himself is the natural philosopher of physicos. And we said several times that person

is meant to be investigating causes and he's also very clear that what is the principal cause that this natural philosopher is supposed to be looking for. And that is the cause for the sake of which the telos, the purpose and he very much wants to sort of prove his maxim

that nature does nothing in vain and is a very large extent to which that's what the biological works are all about. And the animals are sort of the one of the places where you can really see that there is a beginning and a process that's leading to a clear purpose in the sense

from the sperm going all the way to the grown animal. Amor, how far can we use the word, we're already using the word scientists, which didn't come into the 1830s, but how far can we use the word revolutionary about Aristotle as a thinker in this area? Oh, I mean, for me, the difference between himself and his predecessors

could not be greater. There are others who would argue that he is mere epigone to Plato, a mere footnote to Plato, as indeed are all philosophers. But for me, the difference couldn't be greater, and also to his other pre-Socratics. So as I argued, though not everybody would agree with me in this, Plato hates the empirical world. He's completely uninterested in these forms that exist in a realm beyond the senses,

and that is as his anti-scientific of philosophy as can possibly be imagined. If you want to be a scientist, you've got to be interested in this world. All men desire to know, says Aristotle. And he means that all men have wished to perceive through their senses. That's what's important. And then we have the other philosophers who just gaze down as if from Olympus are speculating about the world, but who refuse to get their hands dirty. What Aristotle does is he takes theory and observation, he puts them together and makes science.

Who did he influence, Sophia? So his immediate student and co-worker was Theophrastus, who took over his school. And Theophrastus was assigned to look at plants. And he continued on in some of the same methodology and gathered together huge amounts of information about plants and talked about the causes of plants. He moved on a little bit and then looked at the characters of animals, which was something that Aristotle considers in his historic animal, when he's gathering all of his information. together. And he doesn't actually write an explanatory treatise,

but Theophrastus moves on to do that. But after that period, his biology really gets sidelined for various different reasons. It gets used as a kind of source book for stories, but not treated as a theoretical works. There's this big project of putting Aristotle and Plato together in late antiquity. And in order to do that, you kind of have to side.

sideline the biology and emphasize the more abstract bits of Aristotle. And so he really gets pushed aside until probably the Arabs pick him up. And Avicenna is very familiar with his work and does some brilliant work on the biological works. And then they come back to us through the Arabs in the 13th century. And then it's more piecemeal because in the Renaissance, you have people arguing against him. But you also have William Harvey, who's very interested in his work, especially in embryology. He doesn't agree with everything. But he takes up this epigenesis, this development of the embryo from kind of undifferentiated mass to complicated animals.

And meanwhile, his effect on people's thinking where they use logic digs in in the early medieval recess and continues for hundreds of years after that. If you heard to say Merto about his legacy today, what would you say? On legacy today, well, there's been, I mean, in between, there's been so much sort of science being done that was so much anti-Aristol because of all the stuff about sort of the earth being in the center of the universe. And it was sort of, there's been a sort of a long time where science was trying to fight against Aristotle. and also in all the material about sort of generation and the inferiority of the female and all that sort of thing. But, I mean, what I find most fascinating and what I think makes him most worth studying is sort of the sheer breadth of everything he did

because it's not just the biological works. This is a man who's sort of, you know, done serious logic, serious metaphysics, all the way to politics and literary criticism, all of that under one umbrella. That's a fascinating range. And just to remind ourselves of his famous sort of protreptych to biology, where he says that, you know, you can find knowledge and get great pleasure from knowledge even from the smallest, ugliest animals. So not leave anything aside.

I think that's a great piece of legacy, that everything in nature is worth studying. Well, thank you very much. Thank you very much, Mr. Hazemakali, Sophia Conall, and Amon L'Aroix. Next week, what inspired you? so many artists to paint the Bible story of Judith beheading, Holofernes, among them Garavaggio and Klimt. Thanks for listening. And the In Our Time podcast gets some extra time now with a few minutes of bonus material from Melvin and his guests.

Perhaps something a bit more about the whole nature does nothing in vain point. And I think it's worth saying to people that Aristotle has this quite strange balance that he's trying to strike, on the one hand, trying to say that everything is done for a purpose in nature and animals are the best demonstration of that. And at the same time, not wanting to admit

any kind of creator, any kind of provident God, any kind of that. So trying to say both of those things at the same time is one of the really interesting things. He thought there's a prime mover, but he didn't think there was a God. That's right. The prime mover is not, I mean, is as close, yes, as close as it gets to a god.

but he's not actively doing anything. He's not moving. He's not, he, I mean, we're saying he, the prime mover is fundamentally unmoved. There is a kind of pseudo-intentionality in nature. So the way that it, when I was saying that nature is aiming towards an end, and the end is the, for the sake of that animal, that particular animal, its life.

It's as if there was somebody choosing along the way to, facilitate that end, but there isn't. So nature is a kind of pseudo-intentional agent here. But there's also no overarching nature. He doesn't think that all animals are for the sake of humans or animals are the sake of God or something like that. Yeah, so that's the wonderful and strange thing about Aristotle's biology. When you start getting into its metaphysics, So he's not an evolutionist. He's not a creationist either. He's an eternalist, which is an altogether weird thing.

He just thinks the world's been ticking over and all the animals in it since, well, not since any time. It's just forever and forever and forever. And we can hardly wrap our heads around this because we think of science as being structured. We think of, you know, creationist versus evolutionists. One of them's got to be right. Well, we know evolutionists, right? But he's something else. And he speaks about design all the time.

but he's very clear there is no designer, right? I mean, it's, so there's all these sorts of paradoxes, and then when you push beyond it, what you get into is this weird astro theology in which he argues that the stars themselves are alive. They're actually living creatures, which are more perfect than us. They're having a good time up there,

and they're rotating around, and the reason that all creatures reproduce and are adapted in the way that Sophia described to their various ends, and they're described, is because they want to be like those divine, creatures of they're like the prime movement. I mean, it's all weird.

So the heavenly bodies are very simple living beings. They're not animals. They only have locomotion and they don't have any other change. And they are eternal, so they don't come to be and pass away. There was something I wanted to mention about that, which is that animal, this teleology is mostly about the individual animal,

but it does go beyond. the individual, when they are striving to produce another the same in form. And this is how animals are eternal. This is the way that they can participate in being eternal is by producing another the same in kind because we have these kinds that exist all the time forever. Exactly. And once you give the premise that it has to be eternal, well then from there, all the other teleology flows. Because if you want to be eternal, you've got to survive, you've got to be reproduce and therefore you've got to be fitted to your environment. Your birds have to have the right kind

of beaks and the legs and all that sort of stuff. And that gives you the whole adaptationist panoply so that it reads like Darwin but without natural selection and that's what makes them so enticing for a zoologist. Being is better than not being. That's how he puts it. Being is better than not being. Yes.

Living is better than not living. Yes. And so forth. But once we start getting into all of that actually Aristotle is a bit closer to Plato than we might have thought so far. So he values, I mean, this kind of, this material about sort of imitating the divine as best we can is exactly paralleled in Plato. But always with the designer missing out, whereas Plato does have a divine creator and so forth. With Aristotle, we get the same sort of ideas, the same sort of goal directedness, but without the designer, as Amand was saying.

Christianity embraced Plato in the way in which they didn't embrace Aristotle. Yes, and that's got a lot to do precisely with all those things, with the lack of creator, the eternity of the world. That's one of the big things that Christians sort of got after Aristotle for. The Neoplatonists as well. Yes, exactly. Philoponus was a Christian, yeah. One of the ways in which he diverges from modern biology is that modern biology is anti-teleological, anti-essentialist,

evolutionary theory concentrates on populations and genetic codes but not individuals so I wanted to hear more from Armand about what he thinks Aristotle can contribute to modern biology or

Aristotelian I would disagree that Aristotle is so different from modern biology in the so-called essentialism or his teleology I'm not entirely sure what you mean by teleology is a bit of a fraught word but for me I take a that it's simply the idea that things are designed for some end,

a functional end, and that creatures in the course of the development execute some program, which causes them to have shapes such that they can carry out those ends, such that birds have particular kinds of bells and beaks and legs and so on and so forth. From that point of view, I regard biology as teleological as Aristotle, absolutely. So evolution can't do without an idea of form in some sense. Form and design, absolutely not. Because then that's the way you will explain.

Absolutely. Now, the only way we differ from Aristotle, of course, is how we actually get there, right? And, you know, as to the explanation for why it exists. But I regard that Aristotle as being relentlessly theological. It has often said also that Aristotle is very essentialist. You said so you suggested this. But I suppose what you mean is that what really matters is some sort of an essential form that a species has and that all the variation among individuals is unimportant.

Is something like that? As opposed to the modern view, which embraces all that variation. Again, I think that's, it is certainly not consistent throughout Aristotle. I mean, consider Francis' theory of inheritance, which it gives in the best theory of inheritance, I think, before Mendel, in which he accounts for and explains why people have different noses, for example. I'm sure you can go for hours and listeners would love you too

but the producer has got to come in brutally cut this off. In our time with Melvin Bragg is produced by Simon Tillotson. It's 1994 and two pop stars are flying to a remote Scottish island. Is your seatbelt on tommy? With two suitcases

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