From the preceding it should appear, that the most comprehensive formula to which life is reducible, would be that of the internal copula of bodies, or (if we may venture to borrow a phrase from the Platonic school) the _power_ which discloses itself from within as a principle of _unity_ in the _many_. But that there is a physiognomy in words, which, without reference to their fitness or necessity, make unfavorable as well as favorable impressions, and that every unusual term in an abstruse research incurs the risk of being denominated jargon, I should at the same time have borrowed a scholastic _term_, and defined life _absolutely_, as the principle of unity in _multeity_, as far as the former, the unity to wit, is produced _ab intra_; but _eminently_ (_sensu eminenti_), I define life as _the principle of individuation_, or the power which unites a given _all_ into a _whole_ that is presupposed by all its parts. The link that combines the two, and acts throughout both, will, of course, be defined by the _tendency_ to _individuation_. Thus, from its utmost _latency_, in which life is one with the elementary powers of mechanism, that is, with the powers of mechanism considered as qualitative and actually synthetic, to its highest manifestation, (in which, as the _vis vitæ vivida_, or life _as_ life, it subordinates and modifies these powers, becoming contra-distinguished from mechanism,(9) _ab extra_, under the form of organization,) there is an ascending series of intermediate classes, and of analogous gradations in each class. To a reflecting mind, indeed, the very fact that the powers peculiar to life in living animals _include_ cohesion, elasticity, &c. (or, in the words of a late publication, "that living matter exhibits these physical properties,"(10)) would demonstrate that, in the truth of things, they are homogeneous, and that both the classes are but degrees and different dignities of one and the same tendency. For the latter are not subjected to the former as a lever, or walking-stick to the muscles; the more intense the life is, the less does _elasticity_, for instance, appear _as_ elasticity. It sinks down into the nearest approach to its _physical_ form by a series of degrees from the contraction and elongation of the irritable muscle to the physical hardness of the insensitive nail. The lower powers are _assimilated_, not merely _employed_, and assimilation presupposes the homogeneous nature of the thing assimilated; else it is a miracle, only not the same as that of a _creation_, because it would imply that additional and equal miracle of annihilation. In short, all the impossibilities which the acutest of the reformed Divines have detected in the hypothesis of transubstantiation would apply, _totidem verbis et syllabis_, to that of assimilation, if the objects and the agents were really heterogeneous. Unless, therefore, a thing can exhibit properties which do not belong to it, the very admission that living matter exhibits physical properties, includes the further admission, that those _physical_ or dead properties are themselves vital in essence, really _distinct_ but in appearance only _different_; or in absolute contrast with each other.