Maurice Blondel, whose 88 year life spanned almost evenly the last half of the nineteenth and first half of the twentieth centuries, occupies an analogously crucial position in relation to modern philosophy. His connections with Kant and Descartes are complex and critical. Even more interesting, however, is his anticipation and grasp of insights and trends that have become characteristic of contemporary philosophizing. His approach to philosophy is unified by his central insight that its source must be reflection on lived experience and action. For him, human life is “metaphysics in action.” He places himself beyond intelligence and will, at their common source is the dynamism of the person whence they draw their power of action. Such a philosophical effort is necessarily austerely demanding, since reflection can never exhaust the actuality to which it is directed. Blondel used the word action in the same sense in which others were soon to use the word existence. Within this context, he was able to realize and anticipate both the tremendous dignity and the insufficiency of philosophy. In a parallel manner, he realized the enigmatic transcendence of man who “can never suceed in putting into his willed action everything that is at the root of his voluntary activity.” Jean Lacroix has avoided the pitfall of basing his treatment of Blondel exclusively on an analysis of L’Action, which is only one Blondel part, if the best known element, of the Blondelian corpus. His analysis takes full account of the other three elements of what Blondel called his “tetralogy” : La Pensee, L’Etre tt les etres, and La Philosophie et l”Esprit Chretien.