intelligence and free-will, apparently by including it in the closest connection with the second, that of reason, as the highest degree of the consciousness already given, with sensation. The second problem, B, that of sensation, on the other hand, he holds to be unsolvable. I grant that one might more readily enlighten me, if he should say to me: 'A, that is life, is and must remain inexplainable; but that once given, sensation and thought follow of—themselves that is, by natural development'; or, if it were stated in the inverse sense, 'A and B may indeed be comprehended, but the understanding is strained at C, or self-consciousness.' Either of these views appears to me more acceptable than the one that the middle station only is impassable."
Strauss has not touched the marrow of my observation. I called astronomical knowledge of a material system such knowledge as we might have of the planetary system, if all the observations were accurate and all the difficulties of the theory overcome. If we had astronomical knowledge of what is going on in ever so obscure an organ of the animal or vegetable body, our demand for a causal agency would be as well satisfied, so far as the nature of our intellect permits with reference to that organ, as with reference to the planetary system; but, if we had astronomical knowledge of what occurs within the brain, we would still not be advanced a hair's breadth with reference to the origin of consciousness. In regard to these problems, Laplace and Leibnitz, whose minds were so immeasurably superior, yet similar to ours, were no wiser than we; and if Leibnitz had realized his fiction that he could compose a homunculus, atom by atom, molecule by molecule, he might, perhaps, make his creature think, but not comprehend how it thought.
The primary origin of life in itself has nothing to do with consciousness, but is a question only of the arrangement of atoms and molecules and of the production of certain movements. Consequently, not only is astronomical knowledge thinkable of what we call original production, spontaneous or equivocal generation, or heterogeny, but it would satisfy our demand for a causal agency for the primary origin of life as well as in regard to the motions of the heavenly bodies. This is why, speaking with Strauss, "in the ascending development of nature" the gap in our apprehension does not open at the point A, but at B. I have not maintained that, sensation being given, every higher stage of mental development becomes comprehensible; that problem C is made solvable without further steps. I attached weight to the incomprehensibility of the simplest sensations on mechanical grounds, only because the incomprehensibility of all the higher mental processes follows from it by an a fortiori argument.
The origin of life seems to have become veiled in a deeper obscurity since men have hoped with the aid of the microscope to see the living come from the dead in their laboratories. According to M. Pasteur's researches, heterogeny is underlaid by panspermy, and, where life was