As a rule books of this sort -- primers on philosophic matters -- are really refugees from prep school encyclopedias. But here the author has produced a valuable vade for both the college student and the interested layman. Above all, footnote waywardness has wisely been ditched in order to concentrate on the dominant issues of the periods covered which run from the Copernican revolution onward through the various systems constituting modern thought. The style is energetic, forthright and sober.