November 26, 1909] 



SCIENCE- 



765 



going on; or it may refer to the antecedent 

 processes by which organisms came to have 

 that adaptation of form and function to the 

 requirements of their external environment, 

 which has somehow been brought about in the 

 course of evolution. Taken (A) with the 

 former reference, the vitalist's negation might 

 mean any one of three propositions. (1) It 

 might mean merely that vital phenomena are 

 irreducibly unique, in such wise that the laws 

 of their occurrence could never be deduced 

 from even a complete knowledge of the laws 

 of the behavior of matter under all other 

 conditions than those under which these phe- 

 nomena occur. In this sense, vitalism would 

 be a species of "logical pluralism," of the 

 general doctrine of " the heterogeneity and 

 discontinuity of phenomena," which M. J. H. 

 Boex-Borel has just set forth at length in his 

 " Le Pluralisme." Such a doctrine would not 

 be incompatible with a " chemical interpreta- 

 tion " of vital phenomena, so long as they were 

 regarded as the unique modes of action of a 

 unique chemical compound under certain phys- 

 ical conditions — modes of action which no 

 acquaintance with the components separately, 

 nor with other compounds, would have enabled 

 one to predict. In this meaning, which seems 

 to me the most convenient general meaning 

 for the term, many biologists not commonly 

 so called might be classified as vitalists. (2) 

 The vitalistic negation may go farther, and 

 declare that certain peculiarities of the be- 

 havior of matter in organisms can not be 

 regarded as functions of even a unique chem- 

 ical compound with unique modes of action. 

 This might be proved if it could be shown 

 that the peculiarities in question and chem- 

 ical composition are independent variables. 

 Driesch contends that such proof is possible, 

 through an examination of the facts of mor- 

 phology. " Specificity of form as such does 

 not go hand in hand with si)ecificity of chem- 

 ical composition." (3) Chemistry itself, how- 

 ever, is by no means a truly mechanistic sci- 

 ence ; for it has never succeeded in interpreting 

 all its qualitatively diverse phenomena as mere 

 quantitative multiples of the separate proper- 

 ties or modes of action of the individual atoms 



entering into chemical relations. Vitalism 

 may, however, passing by the question whether 

 vital specificities and chemical specificities are 

 correlative, attack the notion of mechanism as 

 such; it may, namely, deny that the properties 

 or activities of an organism can be functions 

 of the presence, in a specific spatial grouping, 

 of a determinate number of physically inter- 

 acting units of matter or energy. It is to the 

 defense of this view that Driesch chiefly de- 

 votes himself. He finds his arguments for it 

 in such facts as the totipotency of isolated 

 blastomeres, and the development of excised 

 portions of the branchial apparatus, of Clavel- 

 lina into small but complete organisms. These 

 facts show that in certain cases part of an 

 organism can do the work of the whole — i. e., 

 produce the typical form ordinarily produced 

 by the interaction of that part with all the 

 other parts. Here, unquestionably, is a per- 

 fect refutation of mechanism in the sense just 

 defined; the facts mentioned constitute a vir- 

 tually tautological proof that, in these cases, 

 morphogenetic processes are not functions of 

 the absolute number of material units present, 

 nor of any single scheme of relative spatial 

 positions of a determinate number of units. 

 Not the single cell, but the whole organism, is 

 the morphological individual; for when the 

 normal number of other cells are present in 

 interaction with a given cell, the cell behaves 

 in one manner; when the other cells are re- 

 moved or transposed it behaves in another 

 manner; but the resultant morphogenesis of 

 the entire organism remains the same, in spite 

 of these diversities of behavior of the single 

 cells composing that organism. In bringing 

 this out so plainly as he has done, Driesch has 

 made a contribution of the first importance to 

 our knowledge of the distinguishing peculiari- 

 ties of living material systems. But it does 

 not follow (as he supposes) from these facts 

 that the specific morphogenetic action of, say, 

 an Echinus egg, may not be a function of 

 some (as yet undetermined) specificity of com- 

 position or structure or physical relations of 

 the original material complex constituting the 

 egg at the moment of fertilization. In other 

 words, Driesch's arguments from morphogen- 



