No dialógo Filebo de Platão:One of the major ontological themes of the work is that there are four kinds of being, or four "elements":

1. O infinito. These are the types of things of which we make relative comparisons such as more or less.
2. O finito. These are the types of things which can be given a definite measurement of number.
3. A mistura kind of being, mixes the first two, limiting and various types of limitless beings in the "world of becoming" and change which people experience, or at least that aspect of it which is not arbitrary and aimless, but a more genuine kind of becoming that aims at being.
4. A causa da mistura genuína, which limits the unlimited beings and orders nature. This, Socrates argues, is reason itself - not only human reason, but the greater reason of nature itself.