ABSTRACT
This chapter examines some arguments-key representative arguments-for such metaphysical necessities, arguments which try to establish that certain propositions are synthetic a priori truths. In 1957 a number of distinguished British philosophers carried on, over the BBC, a discussion concerning the nature of metaphysics. Peter Strawson and Stuart Hampshire are distinguished articulators of a descriptive metaphysics. They both took part with Ryle in the BBC discussion previously mentioned on the nature of metaphysics. So the vindication of metaphysics rests on being able to establish the truth of synthetic a priori propositions and indeed synthetic a priori propositions of sufficient importance to count as metaphysical propositions yielding metaphysical knowledge. Metaphysicians, in a full-bodied sense of "metaphysics" (i.e., transcendental metaphysics), are rationalists and they minimally want there to be certain propositions about ultimate reality that are absolutely certain. Maximally, they want a total system that is completely comprehensive and is known with absolute certainty to be "the total truth.".
