8 GENERAL HISTOLOGY. 



death is resisted," which is merely asserting that life and death 

 are opposite states. 



Dr. Carpenter says that life is the " condition of a being 

 which exhibits vital actions." This is only another way of 

 saying that life is a state of living. 



Coleridge called life "the principle of individuation." This 

 is equivalent to separate existence and applies to stones, 

 metals and everything else. 



Herbert Spencer says life is "the continuous adjustment of 

 internal relations to external relations," a description which 

 will apply to a steam engine, a burning candle, or a boiling 

 teakettle, as well as to a living thing. 



All such definitions evade the real question " What is the 

 cause of the difference between the living and the non- 

 living?" 



The only answer which we deem reasonable is that of a 

 rational dualism, viz., that a living being is the manifestation 

 of a spiritual existence in the sphere of the physical world. 

 In other words, life is the influence of the soul upon the body. 

 This opinion is the most ancient and universal one, held in all 

 ages, and maintained at the present day by the great majority 

 of educated and uneducated men of all creeds and nations. 

 The identity of psychic and vital force is rendered probable if 

 not certain by the intimate relation between organic and men- 

 tal functions. Anatomy has found no bodily organ forthought, 

 affection or will, yet these mental processes are enfeebled by 

 exhaustion of the bodily powers, except where there is organic 

 defect. The mutual influence of body and mind is matter 

 of daily observation. 



II. THE HISTOLOGICAL UNIT. 



I. The old division of bodies into organized and unorgan- 

 ized, as synonyms of the living and non-living, from the pres- 

 ence or absence of organs, or distinct parts with definite 

 structure capable of special use, is no longer applicable, since 

 only a small part of an organism is truly alive. A dead twig, 

 or bone, or muscle, may be called organized when no part of 

 it is alive. The organic crystals found in plants, or in patho- 



