July 15, 1904.] 



SCIENCE. 



89 



formulated often develops in the contrary di- 

 rection, from the abstract to the concrete. 

 Generalizations built of facts are not abstrac- 

 tions, but collective facts, while the words in 

 which they are expressed nearly always trace 

 their origins back to primitive abstractions. 

 ' Eorce ' was originally a mere synonym of 

 ' strength,' but has now become, in the minds 

 of many, a physical entity, and 'heredity' or 

 ' heirship ' is actualized into a determining 

 ' principle ' of evolution. Philosophy came be- 

 fore science, metaphysics before physics and 

 physics before biology, in the history of prog- 

 ress from the abstract to the concrete. The 

 phenomena of personality are most familiar, 

 but they have received the slightest scientific 

 attention; in the phenomena of life we also 

 participate, but have only begun to generalize, 

 while the phenomena and theories of unorgan- 

 ized matter are formulated almost as exten- 

 sively as those of metaphysics, and with the 

 assistance of as many abstractions. Kecent 

 discussions of the constitution of matter read 

 like metaphysical treatises, lacking only a 

 certain ponderous assumption of certitude. 

 The idealistic physicists argue that matter is 

 electrical, while the materialists suspect that 

 electricity may be material. 



Forces and Properties. — In dealing with un- 

 organized matter the physicist has an apparent 

 advantage over the biologist, since he is able to 

 command definite quantities and uniform ma- 

 terials and conditions of experiment, and thus 

 secures results which can be stated in mathe- 

 matical form, but this has not given him, as 

 yet, an adequate insight into the nature and 

 causal relations of the phenomena with which 

 he deals. It is not the physicists who are at- 

 tempting to extend their practice into biology, 

 but the biologists who insist on paying tribute 

 to physics, even after such an eminent spe- 

 cialist as Lord Kelvin has pronounced their 

 case hopeless, unless recourse be had to other 

 ' forces ' than those at his professional com- 

 mand. 



Physicists are willing to recommend ' vital 

 principle' as an aid in biological difficulties 

 because similar ' hypothetical entities ' are 

 much used to assist in the formulation of 



physical facts. That ' vital force ' does not 

 really explain anything is no objection to it 

 from the physical standpoint; neither do other 

 ' force ' abstractions. Their function is merely 

 to assist the mind to follow ascertained se- 

 quences of facts; they are our algebraic sub- 

 stitutes for unknown causal connections. As 

 soon as we thoroughly understand the mechan- 

 ism, the instinct of causality is satisfied and 

 the hypothetical ' force ' becomes superfluous ; 

 it is useful only if it assists observation and 

 experiment. The pld vital force which ' ter- 

 ribly hampered ' biological investigation was a 

 thoroughly bad abstraction, and has been con- 

 signed to a merited oblivion. The unwilling- 

 ness of biologists to restore this idol or to 

 set up another in its place should not, how- 

 ever, lead them to ascribe any superior virtue 

 to the gods of the physicists, unequally doomed 

 to dethronement. 



Physicians have long since given over gen- 

 eral theories of disease and are reconciled to 

 treating symptoms and removing causes. 

 When other branches of science have received 

 a similar amount of study they may be con- 

 tent with phenomena and leave the ' entities ' 

 to the metaphysicians. Phenomena, instead of 

 being assigned to unknown entities, are more 

 conveniently and practically classified into 

 groups called properties, and in biology we 

 are ready to give up the notion that each 

 property or group of phenomena must have a 

 ' force ' or other hypothetical entity behind it. 

 The perception has come that the properties 

 of life are not distinct ' forces,' but are merely 

 different aspects of the same vital process. It 

 is as a process rather than as a ' force ' that 

 life appears to lie beyond the phenomena of 

 physics. 



It did not improve matters to analyze evolu- 

 tion into two hypothetical opposing ' forces,' 

 heredity and variation, or heredity and en- 

 vironment; these abstractions have long con- 

 cealed the universal facts that organisms fol- 

 low each other in series of similar but not 

 identical individuals, and that species are not 

 merely influenced by environment, but are 

 normally in motion. There is no heredity 

 which keeps organisms exactly alike, nor any 



