LIVING SUBSTANCE 119 



provided with extremely delicate silicious skeletons, in many 

 tissue-cells when pressed close together into polyhedral forms, 

 and in many spherical egg-cells ; and, in the second place, in 

 inorganic nature the mathematically fixed body-form is wanting 

 in all fluids. 



Farther, it has been maintained that inorganic bodies, such as 

 crystals, have no organs, while the presence of these distinguishes 

 all organisms. This also is incorrect. There exist not only 

 organisms without proper organs, such as Amoeba and all other 

 Rhizopoda, in which the whole liquid protoplasmic body is an 

 organ for all things, but also inorganic structures with real organs, 

 such as machines, in which the individual parts are provided with 

 perfectly definite functions. Yet no one will seriously regard 

 Amaebce as inorganic bodies, or steam-engines as living organisms. 



Another difference has been sought in the claim that, in con- 

 trast to all inorganic bodies, organisms are composed of the charac- 

 teristic structural elements of all living substance, cells. It is true 

 that the cell is a specific element of the whole organic world. 

 But that which characterises this elementary constituent, that 

 which distinguishes it from the whole inorganic world, is not its 

 morphological character. Objects that are composed of separate 

 form-elements can easily be manufactured out of inorganic sub- 

 stances. Nature has manufactured such objects in great quantity 

 in rocks w r hich consist of innumerable separate crystals, such as 

 granite. That which characterises the cell is rather its chemical 

 properties. Hence the presence of cells is not a sign of absolute 

 structural difference. 



Finally, it has been said that inorganic bodies possess a very 

 simple uniform structure, while organisms possess a highly complex 

 " organisation." If by "organisation" there is understood simply 

 the more or less complex composition of organisms out of different 

 kinds of elementary structural particles, the cells, this state- 

 ment, within certain limits, is true ; although, in contrast with 

 composite rocks, the difference is merely one of degree. But the 

 cell must be employed for comparison, for it is in itself a complete 

 organism. If, however, the conception of complex " organisation " 

 be applied to the cell, it signifies merely the gross morphological 

 variety and chemical complexity of its constituents, and such a 

 condition can be established in a test-tube in a complex chemico- 

 physical mixture. If by "organisation" a special kind of associa- 

 tion of the individual constituents is understood, such as would 

 not occur in inorganic nature, then the conception carries with it 

 more or less mysticism, which has always been a favourite aid in 

 explaining vital phenomena. Such a process cannot be followed 

 in science, for science and mysticism are mutually exclusive. 



Thus it is seen that a comparison of the structural relations 

 of living and of inorganic substance does not reveal essential 



