Atomism is explored in Plato's dialogue Timaeus and was also supported by Aristotle. Andrew Pyle gives a lucid account of infinite divisibility in the first few pages of his "Atomism and its Critics". There he shows how infinite divisibility involves the idea that there is some extended item, such as an apple, which can be divided infinitely many times, where one never divides down to point, or to atoms of any sort. Many professional philosophers claim that infinite divisibility involves either a collection of "an infinite number of items" (since there are infinite divisions, there must be an infinite collection of objects), or (more rarely), "point-sized items", or both. Pyle states that the mathematics of infinitely divisible extensions involve neither of these — that there are infinite divisions, but only finite collections of objects and they never are divided down to point extension-less items.