Aristotle and Plato’s Forms
Aristotle (c. 384-322 B.C.E.) is perhaps the most preeminent Western philosopher of all time. Among his peers stands his teacher at the Academy of Athens, Plato, many of whose metaphysical theories Aristotle came to criticise and refute in his later life and works. Chiefly among these is the abstract Platonic notion of the ‘Forms’ (sometimes referred to as ‘Ideas’), which Plato devised during his middle dialogues to explain the essential nature of all knowledge. The Forms themselves (Man, Beauty, Large, Round, etc.) are said to exist outside of space and time – the realm of ordinary perception and experience – and, therefore, contain no spatial or temporal parts. According to Plato, the Forms further explain how we can know certain things to be true and where (in a modal sense) their objective nature is to be grounded.
A key feature of Plato’s late dialogues is the firm suggestion that he somehow reconsidered his theory of Forms. Although there seems, in the late dialogues, to be a theory of Forms of some sort (although the theory is wholly unmentioned in the Theaetetus and the Laws), it seems in several ways to have been modified from its conception in the middle dialogues (particularly the Phaedo and the Republic). Perhaps the most remarkable sign of such a change in the theory appears first in the Parmenides, which seems to subject the middle-period version of the theory to a kind of Socratic refutation. Only this time, the main refuter is the Eleatic philosopher, Parmenides, and the interlocutor receiving the refutation is the younger Socrates.
The most well-known of the arguments provided by Plato’s Parmenides in this dialogue is the ‘Third Man Argument’, which suggests that the conception of participation (by which individual objects take on the characters of the Forms) falls victim to an infinite regress: if individual male things are male in virtue of participation in the Form of Man, and the Form of Man is itself masculine, then what is common to both the Form of Man and the particular male things must be that they all participate in some (other) Form, say, Man II. But then, if Man II is masculine, then what it has in common with the other masculine things is participation in some further Form, Man III, and so on. Because Plato’s theory is open to this problem it derives its character from the notion, mentioned above, that Forms are universals. If the Form of Man is itself a masculine, then the Form shares in common a property with the males that participate in it. But, since the theory requires that for any group of entities with a common property there is a Form to explain the commonality, it appears that the theory does indeed suffer from a vicious regress.
There has been considerable controversy for many years over whether Plato believed that the theory of Forms was vulnerable to the Third Man Argument, as Aristotle indeed believed it was. So Plato either uses the Parmenides to announce his rejection of the theory of Forms, or instead he believes that the Third Man argument can be avoided by making adjustments to the theory. Of relevance to this discussion are the coincidental dates of the Timaeus and the Parmenides, since the theory of Forms of the middle dialogues also play a prominent role in the Timaeus. The position of the later date to the Timaeus shows that Plato may not have regarded objections to the theory of Forms, which appear in the Parmenides to be particularly troublesome.
In any case, Aristotle regarded Plato’s theory as inadequate because he saw no tangible connection between Forms (being transcendental and other-worldly) and the practical, material world of substances (that which humans experience). Aristotle also held that the theory of Forms was unable to adequately account for generation, change and destruction. Herein, in departing from Plato’s Parmenidean stance and adopting a more Heraclitean position, he proposed that the Forms are imminent in objects and not in another realm of existence. In accepting change as being a genuine part of reality, Aristotle observed that nothing potential can bring itself to change without the agency of one or another of the four ‘causes’ (material, formal, efficient and final). In terms of an over-arching ‘first cause’ to everything, Aristotle rejected Plato’s Form of the Good (the highest in the hierarchy of Plato’s Forms or the ‘Super-Form’) as irrelevant to the affairs of humans, and indeed, all sentient beings.[1] Instead, Aristotle proposes that there exists an ‘unmoved mover’ which, slightly paradoxically, is a special kind of cause from which everything else is generated. In light of this, Aristotle introduced his explanation of hylomorphism of the material and the immaterial, to which has raised much debate among theologian scholars for over two millennia.
It is important to note that in Plato’s unfinished final dialogue, the Laws, he abandons discussion of the Forms. Whatever value Plato believed that knowledge of abstract entities has for the proper conduct of philosophy, he doesn’t seem to have believed that such knowledge is necessary for the proper running of people’s day-to-day affairs. Indeed, this may seem to mark a departure not only for the later thought of Aristotle (which is more systematic and grounded in the world of human perception, compared to Plato), but also for the ongoing tradition of western thought and philosophy down to the present day.
[1] Audi, 1999. The Cambridge Dictionary of Philosophy, 2nd ed. Cambridge University Press, p. 51.