Philosophy and mathematics grew up together in the days of Pythagoras and Plato. Indeed, they have been in constant companionship and interac-tion ever since. This book examines 15 of these interactions, some deal-ing with the greats of history such as Aristotle and Leibniz, some address-ing modern greats such as Einstein, Schrodinger, and Gödel, and some dealing not with themes, but rather the thinkers. Taken together they rep-resent a characteristic sampling of the author's philosophical investiga-tions over more than three decades.