FACTORS IN OXTOdKNY 247 



to explain a particularly hard prol^lom; one lias siniplv reniov<'<l 

 his problem from the realm of scientific investigation. It is 

 no longer a problem. It is explained— that is, it is explained 

 for whoever accepts the vitalistic assum])tion. 



The varying behavior of things in the inorganic world, tlie 

 functions and ca])acities of these things, dej)en(l on tlu^ varying 

 physical and chemical make-u]) of these things acted upon \)y 

 the various kinds of energy, such as heat, motion, electricity, 

 and what not, which we are more or less familiar witli as a ])art 

 of the physicochemical world, ^'arying energy acting upon, 

 or better, through varying structure: this is the causomechanical 

 explanation of all the phenomena in the inorganic world. 

 Should we not in any o])en-minded consideration of the phe- 

 nomena in the organic world strongly incline to hc)l(l to this 

 same explanation until it is definitely ])roved incomi)etent. 

 untenable? Answering the question with a hearty "Yes," 

 the mechanists look first of all in their study and analysis of 

 the so-called vital phenomena to the matter of structure o( 

 the vital masses and to the play of energy through the masses, 

 to discover, if possible, a tangible clew to the "mysteries" of 

 the life process. In the study of development, then, we strive 

 first to see and to understand the intimate structure of the 

 germ plasm, this protoplasmic stuff with its wondrous endow- 

 ment of potentiality. 



In Chapter III we have already stated sunnnarily what is 

 known of the chemical and j)hysical make-up of protoplasm. 

 What is actually known, by chemical analysis and earn(*st 

 microscopic peering, of this structural make-u}) is wholly in- 

 sufficient to serve as a satisfactory basis of any causomechani- 

 cal explanation of protoplasmic ])roperties. Although some 

 of the simpler capacities of protoi)lasm. as its motion, its 

 taking up of outside substances (feeding), etc.. have been to 

 some degree explained by seeing in them direct physicochem- 

 ical reactions to external stinnili or conditions, practically 

 nothing has been really acc()m})lished as yet toward a mecliani- 

 cal explanation of such more comi)lex or unusual cai)acities 

 as irritabiUty,, assimilation, and reproduction. This last func- 

 tion of protoplasm is in a way its most ai)parently hope- 

 lessly inexplicable property. And this is esi)ecially so when 

 the reproduction is of the sort peculiar to the germinal proto- 

 plasm; that is, where the reproducing protoplasmic mass doe.*^ 



