438 



SCIENTIFIC THOUGHT. 



41. 



Mobility of 

 living 

 matter. 



Another property of all living matter which has been 

 seized upon to furnish a definition of life is its extreme 

 mobility. It has been stated that the great difference 

 between living and non-living matter is this that the 

 former is in a state of movable or dynamical equilib- 

 rium, whereas the latter tends always to a condition 

 of rest or of statical equilibrium. This was especially 

 urged by the late celebrated Du Bois-Reymond of 

 Berlin, to whom we owe the greater part of our know- 

 ledge of the physical and chemical changes exhibited 

 in the active nervous system. In comparison with 

 this property of a dynamical equilibrium, explained by 

 the analogy of a fountain of water or a vortex which 

 change their substance whilst maintaining their form, 

 other older distinctions which had been drawn between 

 organised and unorganised bodies sank into insignificance. 1 



or indirectly." (p. 824). Prof. 

 Japp and Prof. Crum Brown of 

 Edinburgh are of the opposite 

 opinion, inasmuch as in the view 

 of the former "the action of life, 

 which has been excluded during 

 the previous stages of the pro- 

 cess, is introduced the moment 

 the operator begins to pick out 

 the two enantiomorphs," as was 

 done by Jungfleisch. 



1 Among the older discussions 

 of the best way of denning life 

 which belong to the second 

 third of the century, we have 

 in Germany the various writings 

 of Du Bois-Reymond ('Redeu,' 

 notably vol. ii. p. 25) ; in France 

 those of Claude Bernard ('Pheno- 

 menes de la vie,' notably vol. i. p. 

 21, &c.) ; in England the 'Biology' 

 of Mr Herbert Spencer. The two 

 last-named authors examine with 

 some care the definitions of earlier 

 writers. All three should be read 



and re-read by any one who desires 

 to arrive at a clear understanding of 

 the subject. Du Bois-Reymond's 

 definition shows the preponderat- 

 ing influence of the ideas which 

 governed the Berlin school of 

 physiology, and which centred in 

 Helniholtz's tract on the Conserva- 

 tion of Energy. Claude Bernard 

 defines life by the words " La vie, 

 c'est la creation." Organisation 

 and disorganisation are the two 

 sides of this process, organisation 

 and environment the two factors. 

 The doctrine of evolution goes a 

 step farther back, and attempts to 

 analyse "organisation." The pro- 

 cess of creation is to Mr Herbert 

 Spencer a process of development. 

 The word creation in the older sense 

 ceases to have a meaning. Of more 

 recent date are the discussions of 

 the subject in the very interesting 

 work of Carl Hauptmann, 'Die 

 Metaphysik in der modernen Physio- 



