In the previous post we saw how Democritus proposed an atomic theory of matter. Then along came Aristotle who offered an account that assumed that matter can be cut into ever-decreasing size. However, permanence and change had to be accounted for in any explanation of the universe. To do so, Aristotle explained the universe in terms of form and matter. For Aristotle, matter is a pure thing, which has no characteristics at all other than its ability to exist in some form or another. Matter is a permanently existing thing; yet, it can only exist in some form. The form constitutes the appearance of the matter that our senses receive. Anything that exists has to be understood in terms of both its form and its matter. The matter is always present, and the form of the matter is simply the way it is at any given time.
These brief explanations of the ideas of Democritus and Aristotle show how the problem of permanence and change has been dealt with in the past.
Any metaphysical position still needs to account for these basic features of the universe. Indeed, anyone who wishes to construct a metaphysical system needs to somehow account for all the problems that metaphysicians have encountered in the past, many of which are closely related. In some respects, these problems are more difficult now because contemporary science has contributed so much that the present-day metaphysician must take into account. Modern-day science has the same metaphysical problems in some respects.
Quantum mechanics show us that matter can be seen to have atomic properties (i.e., a smallest possible size) and yet also has wavelike properties. It is a similar metaphysical problem,
albeit couched in different terms and within a different context.