But this subject is also an historical subject, living a certain social and economic reality as an objectively defined member of a certain class. As a subject he ‘sums up’ the world, but he sums it up only on the basis of its summation of him. Sartre takes this dimension of the analysis fully into account but, as he says, he has attempted to show the limits of psycho-analytic interpretation and of Marxist explanation, and to demonstrate that it is only through tracing the vicissitudes of a freedom that we can grasp a person in his totality. Through all the conditioning forces, constitutional-somatic, social—historical, it is a freedom that is being conditioned. A freedom that projects itself freely—in compliance with, or rebelliously in the teeth of, all fatedness or determination. This is both the contemporary centre of philosophical concern and the true stuff of biography. Biography is the critical experiment of philosophical hypothesizing. This argument cannot be reduced to the conventional quibbling conceptualizations of free-will versus determinism, nor can it be reduced without fatuity to a lexicographical exercise. It is a matter for concrete demonstration. The truth, when it is discovered, of one man’s life may call the bluff of countless philosophical mystifications.