by Julia Annas
Still less is there the even more notorious idea that nature is there for us to exploit. For Aristotle, skill and expertise take further what nature has begun. He is thinking of farmers who breed grasses to produce food crops, and of cooking as a process of predigestion to enable us to consume otherwise inedible foods. It never occurs to him to think of technology as invasive of nature. (Doubtless this is partly because he is not aware of any technology sophisticated enough to do this.) Nor does it occur to him that human activities might upset nature’s established balances. Humans hunt and eat animals and fish in the way these hunt one another and eat plants; it is all part of a self-regulating system. Many of Aristotle’s ideas are, tragically, bound to sound quaint in our world, where humans have intervened disastrously in the workings of nature, wrecking ecosystems and exterminating species. For Aristotle the species, including humans, have always been there and always will be; what we want is to understand how they all fit in overall. That is why, in a famous passage, he defends the study of the ‘lower’ animals and how they work as being as worthy a human study as the grander study of the heavenly bodies. ‘For in all natural things there is something wonderful.’
For Aristotle, we want to understand nature, including ourselves as parts of nature, because it is natural for humans to want to understand things. Isn’t this circular, though? Yes, but the circularity does not matter. Aristotle’s theories are naturalistic in the modern sense; they accept that the processes by which we come to understand nature are themselves a part of nature. They are not something mysteriously exempt from the conditions they study. Philosophy, including the study of nature, begins in wonder; we are puzzled and interested by what we find around us, and do not feel satisfied until we have adequate explanations for it. The search for explanation thus does not point beyond itself; for Aristotle it would be beside the point, as well as foolish, for us to try to understand nature in order to exploit it for our own ends. Hence, although different methods are appropriate for studying different areas of nature, we are puzzled, and seek explanations, in our own case in the same way as happens with other living and non-living things.
Explaining is finding out why things are as they are, and for Aristotle there are four basic ways of doing this, his so-called ‘four causes’, which appeal to what he calls form, matter, the moving cause, and the final cause, what the thing is for.
Teleology without design
Aristotle is aware that his demand for teleological explanations, explanations in terms of final causes or what something is for, is contentious. He knows of previous thinkers who held that there are no goals in nature, and that we and the world around us are the contingent products of random events. Animals’ teeth, for example, were held by some to be the product of random combinations of material, some of which turned out to be suited to animals’ needs while others were not.
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Aristotle’s ‘four causes’
Aristotle insists, against what he sees as the narrowness of previous philosophers, that there are four ‘causes’ which the enquirer into nature should make use of. What he has in mind is the different ways in which we explain natural processes and things, and he is insisting that there is not just one type of explanation, but many, which do not exclude one another. Aristotle’s theory, though, is about the way the world is and not just the way we explain it; the four so-called ‘causes’ are different kinds of item which figure in what he thinks are the four fundamental types of explanation of nature.
One is the material cause or matter, the physical make-up of the thing, which puts considerable restrictions on what it can be and do. The second is the form. Aristotle gives examples of artefacts where the form is the shape, but in the case of a living thing the form is more complex: it is, very roughly, the way of being alive which defines that kind of thing. The form of an oak tree is whatever it is which explains why the tree lives and grows as an oak- from acorns, for example, and only in certain climates. Thirdly is the moving cause, the item initiating a change. Fourthly is the final cause or end, what the thing or process is for, something that has to be cited in showing how it functions.
Modern theories of causality have very different aims and assumptions, and would count only Aristotle’s moving cause as a cause (and only with qualifications).
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Aristotle, as often, does not think that this story is completely wrong; we do need the right kind of physical embodiment. But on its own it is inadequate to explain why we always (or nearly always) find that animals are well adapted to the lives they lead, and that their parts are formed in a way which performs the appropriate function. Teeth, for example: we find the sharp incisors at the front of the mouth, for tearing, and the blunt molars at the back, for chewing. We always find this, because it is a good arrangement for the animal. Unless something has gone wrong, we don’t find animals struggling with bad arrangements (molars at the front, for example). Random happenings, Aristotle thinks, are quite inadequate as an explanation of how we get to the universal well-adaptedness to environments and lifestyles that we find among animals. Thus, he concludes, our explanations have to include what the thing is for. Aristotle does not think that this is always appropriate: there is nothing, for example, that horses or camels are for. The level of explanation that concerns him is that of the parts of animals. Hearts, for example, are for pumping out the blood to the rest of the body; blood, in turn, is for carrying nutriment to the body.
Aristotle’s is an especially interesting position, because we can now appreciate both that he is wrong, and that at the time he had the better of the argument. In the absence of any plausible mechanism for getting to (almost) universal well-adaptedness from random happenings, as well as the absence of any idea of geological time, Aristotle is right in thinking that present well-adaptedness cannot be accounted for merely by random happenings. After Darwin’s work, we can see why we are not compelled to an Aristotelian view by the kind of consideration that Aristotle stresses.
Aristotle’s teleological approach is the source of his most sympathetic insights. In plants, he comments, the roots have the function that the head has in animals; but we should not think of plants as growing upside down, since what is up and what down depends on the kind of thing we are talking about. Crabs are the only animals which move sideways; but in a sense they are moving forwards, since their eyes are so positioned that they can see where they are going. In these and many other cases Aristotle frees himself from human ways of thinking of things like nutrition and movement to observe how well the species functions from its own point of view.
Aristotle’s thoughts about teleology have nothing to do with the idea that purposes in nature are the product of design – indeed, for him this would be inappropriate projection of human concerns onto nature, shaping nature in our image in an absurdly pretentious way. But Aristotle’s was not the only version of teleology available in the ancient world.
Teleology with design
In his dialogue Timaeus, Plato presents an account of the universe as created by God, who is a craftsman and who produces our universe in the way that a craft worker creates an artefact, by imposing form and order on materials which are more or less satisfactory for the task. Plato holds that the materials available to God for making the world are inherently unsatisfactory and perhaps even refractory, since our world is created to a good plan, but contains failure and evil.
It is uncertain, and was much discussed in the ancient world, whether Plato had in mind an actual creation or was merely giving an analysis of the ways things are, but certainly the overall picture is one in which our world is not just created, but created to carry out an intellectual design on the part of a creator. Moreover, not merely the general principles of cosmology, but some quite specific details, particularly concerning humans, are explained in terms of overall design. The fact that humans walk upright, and have roughly spherical heads, is explained by reference to our being rational in a way that other animals are not; the e
xplanations, as we might expect, are extremely fanciful.
The Timaeus, however, presents itself not as serious cosmology but merely as a ‘likely story’, an example of the kind of account that Plato thinks is the right one to give; it is poetic and grandiose in style. And the account it gives is also very openly ‘top-down’, working through the consequences of a few very general principles; Plato shows no interest in satisfying the observations we make in our experience, or in making any himself.
The Stoics picked up on Plato’s account of the world as the creation of a designer God, and developed it, though in a somewhat different direction. Their conception of God is different; for them God is to be thought of not as a creator of the world, but in a more impersonal way. God is simply the rational organization of the world, and so should not be thought of on the model of a person (though the Stoics allow that popular religion, which accepts several gods, is a dim grasp of the idea that the world is structured by reason and intelligence).
The Stoics therefore take a different tack from Plato’s appeal to the idea that God is like a craftsman. They appeal to evidence in the world that suggests that it is the product of design and rational ordering. They reject the idea that the world is the product of random events and forces, on the grounds that it is implausible – like, they say, the idea that random distribution of letters of the alphabet could produce a poem. (Note that this argument is different from Aristotle’s; he denies that random events could produce regular well-adaptedness, whereas the Stoics deny that random events could produce good design.)
Some of their arguments for design in the world appeal to the sheer complexity of natural objects. Suppose, one argument goes, that a complicated mechanism like a clock were shown to people unfamiliar with it; they would still recognize it as the product of a rational being. Hence, natural objects, which display a greater complexity and suitability for their function than artefacts, must be the product of reason – clearly a reason greater than ours, one embodied in the universe as a whole. (This is strikingly similar to the ‘argument from design’ common among Christian thinkers before Darwin.)
Other arguments appeal to the complexity of the world’s organization, seen as a huge ecosystem in which all the parts are mutually interdependent. The Stoics also appeal to the way that animals are well-suited to their environments and mutual interrelations, but they are not interested in these for their own sakes, merely for the indication they give that the world is a well-organized whole.
Thinking of the world as designed, the Stoics often compare it to a house or a city, and since these are obviously designed for the sake of their inhabitants, this makes prominent the point that for the Stoics the world is rationally designed for the obvious beneficiaries, namely rational beings – that is, gods and humans. As far as humans are concerned, therefore, the rest of the world – plants and animals – is designed for our benefit. This leads the Stoics to a very anthropocentric view of the world, in which grain, olives and vines are for us to consume, sheep for clothing us with their fleeces, oxen for pulling our ploughs and so forth. Such a world-view is almost guaranteed to kill the curiosity about nature’s wonders that we find in Aristotle, and it leads to an exploitative attitude to the rest of the natural world, a strikingly ugly contrast to the humanitarian attitude we find in Stoic thought to all humans, whatever their social roles.
No teleology?
Epicurus alone among the ancient schools denies that in nature we find any teleological explanations. Nothing in nature is for anything, neither the world as a whole nor anything in it.
Positively, Epicurus asserts that our world, and in the course of time infinitely many worlds, have grown up as a result of random collisions of atoms in empty space. This is, he claims, a sufficient explanation, given enough time. We have seen that given the state of other beliefs about the world in ancient culture (for example the absence of any indication of the real age of the world), Epicurus’ position here was bound to seem weaker than it does to us, and one reason that one or other form of teleology was so common in ancient thought was just the implausibility of the alternative.
Epicurus also argues against the opposition, and here appeals to the idea that an unbiased view of our world does not make it look like the product of design, or at any rate of a very good design. Most of the world is not habitable by humans, for example; human attempts to survive are constantly threatened by the unpredictability of natural factors (droughts, hurricanes and so on) and by hostile environments and other species that render human life a struggle. Humans, with their helpless babyhood and lack of natural weapons, do not seem particularly well-adapted to compete for survival with other species. And so on.
Epicurus’ arguments are effective only against the view that the world was providentially designed for the benefit of humans. Even so, there are responses: perhaps the problems humans encounter are due to the fact that rational design in the universe has only inferior materials to order. And Epicurus never really meets the point that with no appeal to any kind of purpose in nature he has a hard time explaining how random collisions of atoms result in the regular well-adaptedness of species to their environments.
Ancient theories and the modern world
The legacy of these ancient disputes became greatly simplified. Already in the ancient world both Jews and Christians found Plato’s Timaeus acceptable as a philosophical explication of the creation story in Genesis. This is not surprising, since the Judaeo-Christian God is the creator of the world, and designed it so as to be good. Moreover, humans have a privileged place in it. In the Middle Ages the view that prevailed was the design view: everything in the world, including us (indeed especially us) was created to fulfil its place in the world, which is to be found in God’s design for it. Humans are the special beneficiaries of this plan, and the rest of creation is designed for us to put to our use.
In the Middle Ages, when Aristotle’s views were rediscovered, they were fitted into the design view, since they were fitted into a theological framework in which the world is the creation of a designer God. Aristotle’s own more subtle position was not appreciated; the only alternatives were seen as being that the world is the result of divine design or that it is the product of mere random happenings. The latter view was not taken seriously until the Renaissance, when Epicurus’ views again became influential and inspired some philosophers to reject the entire medieval world-view.
This world-view included, and indeed had itself largely come to be formed by, the philosophy of Aristotle. But that itself had become greatly altered in the process. Aristotle’s view of nature, including his ideas about ends in nature, had become part of a large theological system. In the process, his own tentative and co-operative methodology was forgotten as his ideas were hardened into a system, increasingly seen as a complete and all-inclusive system, with answers to everything. The medieval poet Dante calls Aristotle ‘the master of those who know’ – in other words, the great know-it-all, something very different in spirit from Aristotle’s own enquiry in a spirit of curiosity and wonder.
The new learning of the Renaissance replaced the system of Aristotelian-ism, but because this had become deeply entrenched in the universities it hung on for surprisingly long, and became associated with self-protective and reactionary rejection of new kinds of thinking. A similar phenomenon happened with Aristotle’s ethical and political thought, which was elevated to a central place by the Roman Catholic Church. This rigidification of Aristotle’s thinking has led to equally unsubtle rejections of his ideas, and to refusal to engage with them in detail. In periods when Aristotle was regarded as The Great Authority, intelligent thinkers have often rejected that authority, while Aristotle’s own attitude has been lost. Because Aristotle’s own works are quite difficult to read, hostile attitudes to his ideas get passed on from book to book, and get accepted by people who have never actually engaged with him as a philosopher. Even today, it is quite common to find sometimes paranoid hostility to Aristotle on the
part of people who have never read more than a few quotations pulled out of context and who think of him simply as an authority to be rejected.
This is an extreme example of the way in which ideas from ancient philosophy can get used and reconfigured by subsequent traditions, in a way which pulls them out of their original context of argument. Sometimes this can be invigorating, and produce a new and fruitful engagement, as happened when Plato’s Republic became a political text in the nineteenth century (see Chapter 2) and with Aristotle for much of the Middle Ages. But if the interpretative tradition goes on too long (especially without serious competition) and gets too rigid and institutionalized, the result can become stultifying, and can end with hostile unthinking rejection. And this makes it harder to get back to the original and engage with it from our own perspective.