The last of Aristotle's claims that we will consider concerns one of Aristotle's many criticisms of Plato's theory of Forms. In the last paragraph on p. 267 (which begins "Further according to the assumption?) Aristotle attempts to refute Plato's conception of the Forms by showing that the Forms share in their particulars just as their particulars share in them. On his account, Plato's theory would generate an infinite regress consisting of an unlimited number of Forms. At about 991a in the Metaphysics, claims that a Form, being predicated of a number of things and existing separately from them, will necessitate something else that is predicated of that Form and all of its particulars. If there is a group of men, they are presumed to be men in virtue of their participation in the Form of Man. This Form, however, must be another example of a man, since it is like all the other examples found in the particulars. Thus, a Form of the Form of Man is needed, and this Form of the Form will itself need a Form. This process will continue forever, involving an infinite regress. is necessitated. Aristotle claims, in short, that the Forms are patterns not only of particular sensible things, but of themselves as well. (990a 30). Any significance that the Forms could hold is lost if there is nothing to distinguish them from particulars. A Form must be, by definition, the single paradigm of a certain class of things. This regress claims that there would have to be multiple Forms for the same class, and even Forms of Forms, making them particulars at the same time. If this is true, then Forms cannot exist in the way Plato conceived of them.
This criticism of Plato's Forms shows that Aristotle grossly misunderstands P ...