Gabriel Marcel’s philosophy is a metaphysical search for "being" as it is discerned in the concrete situation which makes an individual to be. In particular he investigates the sources of "being" in his own life and concludes that man has a twofold mental capacity - to reason and catalogue logically through "primary reflection”, and to arrive intuitively at "being" through "secondary reflection". For Marcel man participates in "being" through relationship with others. There are several degrees of participating and man's spiritual growth demands that he advance from the categories of "having", founded on "primary reflection" and what Marcel calls the "problématique" - reality that falls short of "being". The essential distinction made in this thesis is between man in the grip of "having" and man growing away into "being". "Having" implies that man is alienated from himself, his neighbour and reality, especially through self-consciousness. "Being", on the other hand, requires man to lose egotism and "indisponibilité" and enter into interpersonal relationships. Man can become aware through his ability to recollect himself that he is growing in "being” and therefore saving his soul. "Being” for Marcel must be. It is a continuum from man at one end to the divine at the other, though Marcel leaves it to the individual to identify "being" and God. Marcel's epistemological analysis of man's faculties appears valid, as does his distinction 'between "having” and "being" as an index of spiritual growth. His study of interpersonal relationships is also acceptable. There is some doubt, however, whether "being" is more than a psychological and spiritual state despite Marcel's assertion. "Being" for him is interpersonal, but "being” as he describes it falls short of his own experience of it. Marcel's own intuition of "being" appears to be incommunicable. He also seems to have insufficient regard for man's ability to reason logically. Despite these shortcomings, Marcel's metaphysics can be regarded as making a valuable contribution to man's dignity and personhood.