The Metaphysical Presuppositions of Being-in-the-World brings St. Thomas Aquinas and Martin Heidegger into dialogue and argues for the necessity of Christian philosophy. Through the confrontation of Heideggerian and Thomist thought, it offers an original and comprehensive rethinking of the nature of temporality and the origins of metaphysical inquiry. The book is a careful treatment of the inception and deterioration of the four-fold presuppositions of Thomistic metaphysics: intentionality, causality, finitude, ananke stenai. The analysis of the four-fold has never before been done and it is a central and original contribution of Gilson's book. The four-fold penetrates the issues between the phenomenological approach and the metaphysical vision to arrive at their core and irreconcilable difference. Heidegger's attempt to utilize the fourfold to extrude theology from ontology provides the necessary interpretive impetus to revisit the radical and often misunderstood metaphysics of St. Thomas, through such problems as aeviternity, non-being and tragedy.

"The confrontation between Classical and Heideggerian understanding of Being shows Smith Gilson's superb capacity to get into the mind of philosophers of different schools of thinking and mastering their philosophical language. With great balance, this book neither merges the two in some facile reconciliation, nor makes Heidegger a straw man with which to beat modernity in favor of a 13th century theology, but highlights the similarities and differences of their conceptual frameworks, without getting stuck in terminological equivocalness. The reader will find in these rich and dense pages a sound and substantial dialog between Heidegger's philosophical standpoint and medieval metaphysics." -- Prof. Francisco Fernández Labastida, Pontificia Università della Santa Croce, Italy