[Most philosophers] are at one in affirming the unity of nature, and in representing this unity under an abstract and geometrical form. Between the organized and the unorganized they do not see and they will not see the cleft. Some start from the inorganic and by compounding it with itself claim to form the living; others place life first, and proceed towards matter by a skillfully managed decrescendo; but for both there are only differences of degree in nature – degrees of complexity in the first hypothesis, of intensity in the second. Once this principle is admitted, intelligence becomes as vast as reality; for it is unquestionable that whatever is geometrical in things is entirely accessible to human intelligence, and if the continuity between geometry and the rest is perfect, all the rest must indeed be equally intelligible, equally intelligent. Such is the postulate of most systems. Anyone can easily be convinced of this by comparing doctrines that seem to have no common point, no common measure […].
At the root of these speculations, then, there are the two convictions correlative and complementary, that nature is one and that the function of intellect is to embrace it in its entirety. The faculty of knowing being supposed coextensive with the whole of experience, there can no longer be any question of engendering it. It is already given, and we merely have to use it, as we use our sight to take in the horizon. lt is true that opinions differ as to the value of the result. For some, it is reality itself that the intellect embraces; for others, it is only a phantom. But, phantom or reality, what intelligence grasps is thought to be all that can be attained.
Hence the exaggerated confidence of philosophy in the powers of the individual mind. Whether it is dogmatic or critical, whether it admits the relativity of our knowledge or claims to be established within the absolute, a philosophy is generally the work of a philosopher, a single and unitary vision of the whole. It is to be taken or left.
More modest, and also alone capable of being completed and perfected, is the philosophy we advocate. Human intelligence, as we represent it, is not at all what Plato taught in the allegory of the cave. Its function is not to look at passing shadows nor yet to turn itself round and contemplate the glaring sun. It has something else to do. Harnessed, like yoked oxen, to a heavy task, we feel the play of our muscles and joints, the weight of the plough and the resistance of the soil. To act and to know that we are acting, to come into touch with reality and even to live it, but only in the measure in which it concerns the work that is being accomplished and the furrow that is being ploughed, such is the function of human intelligence. Yet a beneficent fluid bathes us, whence we draw the very force to labour and to live. From this ocean of life, in which we are immersed, we are continually drawing something, and we feel that our being, or at least the intellect that guides it, has been formed therein by a kind of local concentration. Philosophy can only be an effort to dissolve again into the whole. Intelligence, reabsorbed into its principle, may thus live back again its own genesis. But the enterprise cannot be achieved in one stroke; it is necessarily collective and progressive. It consists in an interchange of impressions which, correcting and adding to each other, will end by expanding the humanity in us and making us even transcend it. […]