Freedom is the pillar of the neo-critical philosophy; it is the first truth involved at once in all action and in all knowledge. Truth and error are not well explained, or, indeed, at all explained, by a doctrine which, embracing them both as equally necessary, justifies them equally, and so in a sense verifies both of them. It was this point which Brochard developed in his work _L’Erreur_, which has neo-critical affinities. Man is only capable of science because he is free; it is also because he is free that he is subject to error.[8] Renouvier claims that “we do not avoid error always, but we always _can_ avoid it.”[9] Truth and error can only be explained, he urges, by belief in the ambiguity of futures, movements of thought involving choice between opinions which conflict—in short, by belief in freedom. The calculation of probabilities and the law of the great numbers demonstrates, Renouvier claims, the indetermination of futures, and consciousness is aware of this ambiguity in practical life. This belief in the ambiguity of futures is a condition, he shows, of the exercise of the human consciousness in its moral aspect, and this consciousness in action regards itself as suspended before indetermination—that is, it affirms freedom. This affirmation of freedom Renouvier asserts to be a necessary element of any rational belief whatever. It alone gives moral dignity and supremacy to personality, whose existence is the deepest and most radical of all existences. The personal life in its highest sense and its noblest manifestation is precisely Freedom. Renouvier assures us that there is nothing mysterious or mystical about this freedom. It is not absolute liberty and contingency of all things; it is an attribute of persons. The part played thus freely by personality in the scheme or order of the universe proves to us that that order or scheme is not defined or formed in a predetermined manner; it is only in process of being formed, and our personal efforts are essential factors in its formation. The world is an order which becomes and which is creating itself, not a pre-established order which simply unrolls itself in time. For a proper understanding of the nature of this problem “we are obliged to turn to the practical reason. It is a moral affirmation of freedom which we require; indeed, any other kind of affirmation would, Renouvier maintains, presuppose this. The practical reason must lay down its own basis and that of all true reason, for reason is not divided against itself reason is not something apart from man; it is man, and man is never other than practical—_i.e._, acting.”[10] Considered from this standpoint there are four cases which present themselves to the tribunal of our judgment—namely, the case for freedom, the case against freedom, the case for necessity and the case against necessity. [8] _De L’Erreur_, p. 47. [9] _Psychologie rationnelle_, vol. 2, p. 96. [10] _Psychologie rationnelle_, vol. 2, p 78.