THE P HAS IS OF FORCE. 175 



phenomena ; here, again, those most essential peculiarities of the 

 living body, which involve the temporary subjection of ordinary 

 chemical affinities to some other agency, being entirely passed by. 

 A scarcely less unphilosophical method, however, has been pursued 

 by another class of reasoners, who have cut the Gordian knot by 

 attributing all the actions of living bodies which physics and 

 chemistry cannot account for, to a hypothetical " vital principle ; " 

 an agency which they suppose to exert an autocratic rule in each 

 organism, and whose laws they think it vain to seek. 



By various intelligent physiologists of modern times, however, 

 the dynamical ideas introduced from physics and chemistry have 

 been carried into the domain of life ; and it has been felt that the 

 only mode of placing physiology on a truly scientific basis is, to 

 regard those phenomena which, being altogether peculiar to living 

 bodies, are designated "vital," as the manifestations of a special 

 force or power, and to seek to determine the laws of its operation 

 by the study of its actions. Of all these actions, there is none so 

 universal, and therefore so characteristic, as that by which the 

 organism is built up, or rather builds itself up, from the germ, by 

 the appropriation of materials derived from external sources, and 

 subsequently maintains itself in its characteristic form during its 

 term of life ; hence the hypothetical power which is the supposed 

 source of it, has been designated as the nisus fonnaiivns, the 

 bildimgsirieb, or the oi'ga/Jizing force. This power is usually con- 

 sidered as inherent in the organic structure, and as quite indepen- 

 dent of heat or other agencies external to this, although they are 

 admitted to exert an exciting or modifying influence on its 0];)era- 

 tion ; and it is supposed to be imparted to each individual, like 

 the substance of the germ from which it sprang, by the parental 

 organisms which preceded it. In this point of view, therefore, the 

 germ being potentially the entire organism, all the organizing force 

 required to build up an oak or a palm, an elephant or a whale, 

 must be concentrated in a minute particle only discernible by 

 microscopic aid. But the hypothesis may be disproved by even 

 a more complete rednctio ad absurdum than this ; for if we suppose 

 the whole organizing force to be inherent in the organism itself, 

 and to have been at first derived from its parents, the aggregate of 

 the forces possessed by the several individuals, how numerous so- 



