The general idea is always an abstraction and, for that very reason, in some sort a negation of real life. I have stated in the Appendix that human thought and, in consequence of this, science can grasp and name only the general significance of real facts, their relations, their laws--in short, that which is permanent in their continual transformations--but never their material, individual side, palpitating, so to speak, with reality and life, and therefore fugitive and intangible. Science comprehends the thought of the reality, not reality itself; the thought of life, not life. That is its limit, its only really insuperable limit, because it is founded on the very nature of thought, which is the only organ of science. Upon this nature are based the indisputable rights and grand mission of science, but also its vital impotence and even its mischievous action whenever, through its official licensed representatives, it arrogantly claims the right to govern life. The mission of science is, by observation of the general relations of passing and real facts, to establish the general laws inherent in the development of the phenomena of the physical and social world; it fixes, so to speak, the unchangeable landmarks of humanity's progressive march by indicating the general conditions which it is necessary to rigorously observe and always fatal to ignore or forget. In a word, science is the compass of life; but it is not life. Science is unchangeable, impersonal, general, abstract, insensible, like the laws of which it is but the ideal reproduction, reflected or mental--that is cerebral (using this word to remind us that science itself is but a material product of a material organ, the _brain_). Life is wholly fugitive and temporary, but also wholly palpitating with reality and individuality, sensibility, sufferings, joys, aspirations, needs, and passions. It alone spontaneously creates real things and beings. Science creates nothing; it establishes and recognizes only the creations of life. And every time that scientific men, emerging from their abstract world, mingle with living creation in the real world, all that they propose or create is poor, ridiculously abstract, bloodless and lifeless, still-born, like the _homunculus_ created by Wagner, the pedantic disciple of the immortal Doctor Faust. It follows that the only mission of science is to enlighten life, not to govern it.