  For the Rationalist, mind is for understanding. Understanding is of course connected to pattern detection and prediction, but it also involves making sense of the patterns at some deeper level.  The Classical Rationalist view is that Reason (with a capital ‘R’), in part embodied in our innate endowment, somehow makes this sort of deeper understanding possible.  Descartes’ famous wax example (Descartes 1996/1641) is aimed at making clear the difference between detecting patterns in the flow of perceptual ideas that are prompted by a piece of wax and having a real understanding of what a piece of wax is.  The Humean Empiricist rejects this search for depth as illusory; pattern detection is all understanding is or can be.