Thepurpose of Wissenschaft und Weltanschaunng,1 by Aloys Wenzl, is to provide a rational explanation of the world which shall give us greater insight into its nature than either common sense or the natural sciences can give us. Philosophy, Professor Wenzl says in his introduction, springs from the desire for a weltanschaunng, for insight into the significance of life. But it also springs from a desire for rational explanation, and aims at objective validity. It proposes to give a truer, more complete, and more intelligible account of reality than appearances provide. This idea of a more intelligible explanation underlies the whole of Professor Wenzl's book. We want more than knowledge of empirical facts, we want knowledge of reasons (verstehen aus dem Grund), or, as he often puts it, insight (einsichtig verstehen). We want to see that though things seem to be contingent, they are really necessary.