the rule which these forces observe whenever they enter time and space. But do what we will, the forces themselves remain _qualitates occultæ_. For it is just the thing-in-itself, which, because it is manifested, exhibits these phenomena, which are entirely different from itself. In its manifestation, indeed, it is completely subordinated to the principle of sufficient reason as the form of the idea, but it can never itself be referred to this form, and therefore cannot be fully explained etiologically, can never be completely fathomed. It is certainly perfectly comprehensible so far as it has assumed that form, that is, so far as it is phenomenon, but its inner nature is not in the least explained by the fact that it can thus be comprehended. Therefore the more necessity any knowledge carries with it, the more there is in it of that which cannot be otherwise thought or presented in perception—as, for example, space-relations—the clearer and more sufficing then it is, the less pure objective content it has, or the less reality, properly so called, is given in it. And conversely, the more there is in it which must be conceived as mere chance, and the more it impresses us as given merely empirically, the more proper objectivity and true reality is there in such knowledge, and at the same time, the more that is inexplicable, that is, that cannot be deduced from anything else. It is true that at all times an etiology, unmindful of its real aim, has striven to reduce all organised life to chemism or electricity; all chemism, that is to say quality, again to mechanism (action determined by the shape of the atom), this again sometimes to the object of phoronomy, _i.e._, the combination of time and space, which makes motion possible, sometimes to the object of mere geometry, _i.e._, position in space (much in the same way as we rightly deduce the diminution of an effect from the square of the distance, and the theory of the lever in a purely geometrical manner): geometry may finally be reduced to arithmetic, which, on account of its one dimension, is of all the forms of the principle of sufficient reason, the most intelligible, comprehensible, and completely susceptible of investigation. As instances of the method generally indicated here, we may refer to the atoms of Democritus, the vortex of Descartes, the mechanical physics of Lesage, which towards the end of last century tried to explain both chemical affinities and gravitation mechanically by impact and pressure, as may be seen in detail in “_Lucrèce Neutonien_;” Reil’s form and combination as the cause of animal life, also tends in this direction. Finally, the crude materialism which even now in the middle of the nineteenth century has been served up again under the ignorant delusion that it is original, belongs distinctly to this class. It stupidly denies vital force, and first of all tries to explain the phenomena of life from physical and chemical forces, and those again from