             Aristotle’s approach to the appropriate form of scientific explanation invites reflection upon a troubling epistemological question: how does demonstration begin? If we are to lay out demonstrations such that the less well known is inferred by means of deduction from the better known, then unless we reach rock-bottom, we will evidently be forced either to continue ever backwards towards the increasingly better known, which seems implausibly endless, or lapse into some form of circularity, which seems undesirable.  The alternative seems to be permanent ignorance.  Aristotle contends: