How little life is explained, at least according to the present state of our knowledge, also follows from the _insufficiency of all attempts_ at _defining it_. The latest and most thorough attempt at such a definition of life, with which we are familiar, is that made by Herbert Spencer in his "First Principles", Sec. 25, and in his "Principles of Biology," Vol. I, Part I, Chap. 4 and 5. Having made thorough investigations, he arrives at the general formula: "Life is the continuous adjustment of internal relations to external relations." To this definition we will not make the objection that it is nothing but a logical abstraction from the common quality of all processes and phenomena of life; for it certainly lies in the nature of a definition that it can be nothing else but that. Nevertheless, we will state that such a definition of life not only does not lead us any nearer to the comprehension of its processes, and especially of the richness and the organization of its forms and functions, but that it {140} clearly shows us how little the origin of life is explained. For this very definition necessarily and obviously leads us to the questions: Whence do those internal relations originate, whence their adjustment to external relations, and whence the continuity of this adjustment? The answer to these questions this definition still owes us. Therefore, not only self-consciousness and freedom, not only sensation and consciousness, but also life and the organic, remain a phenomenon which--at least, according to the present state of our knowledge and reasoning--enters into the realm of the world of phenomena as _something new_ that can not be explained from the foregoing, although it presupposes the foregoing as the _condition_, not the cause, of its appearance; and no matter whether we have to think of the modality of its origin as a sudden or as a gradual one. Sec. 4. _The Elements of the World, the Theory of Atoms, and the Mechanical View of the World._ The investigating and thinking mind, when it attempts to explain the appearances and forms of that which exists, finds itself led further and further back, until it finally arrives at the last elements of the world and of matter. Whether we take the problem of life as solved or unsolved, the living has matter and its subordination to the efficiency of all its chemical and mechanical powers in common with the lifeless; and the organic, in its first beginnings, stands extraordinarily near to, and is grown on the ground of, the inorganic,--if not according to the category of cause and effect, still according to that of condition and consequence, of basis and structure. Therefore we stand at last before the {141} question of the final elements of matter, which, indeed, constitutes organic as well as inorganic bodies.