If Aristotle set out to explain more or less the same phase of intellectual development as Plato, the explanation that he gave was very different. In chapter 3 we remarked on one such difference in Aristotle's theory, namely his total rejection of innateness. In this chapter and the next we shall focus on his strikingly un-Platonic optimism about the continuity between the more knowable to us and the more knowable in nature. We shall do this separately for science and ethics, but it will be clear by the end of the next chapter that there are remarkable similarities between his treatment of the two domains.

In the scientific case, the distinction between the more knowable to us and the more knowable in nature is one between a view of the world as presented to us in sense perception and the perspective in which natural phenomena are set in their true explanatory ordering. That the more knowable to us is associated with perception is clear from Physics I 1, 184a16–25, Topics VI 4, 141b10, and An. Po. I 2, 72a1–5 where Aristotle talks of a continuum beginning with the prior for us and ending with the prior in nature, with perception at one end and, at the other, the grasp of first principles. So the distinction between the more knowable to us and the more knowable in nature overlaps with the other distinctions we have seen at work in the last two chapters: the distinction between the cognitive states of perception (or experience) and scientific understanding (or nous), and distinction between the corresponding objects of those states – between the fact and the explanation (or the essence).