340 THE GRAMMAR OF SCIENCE 



recognise that to look upon the mechanical and the 

 conscious as two aspects of one and the same process may- 

 be a distinct simplification of our description of life, and 

 therefore scientifically valid. But I want to point out, 

 and this very earnestly, how the physicist too often entices 

 the biologist into a metaphysical slough by postulating 

 mechanism as the substratum and not as the conceptual 

 description of certain groups of sense-impressions. Had the 

 physicist asserted that the reality of the external world 

 lies for him in the sphere of sense-impressions, and that of 

 the beyond of sense-impression physics knows nothing — 

 had he said : " What I term mechanism and Professor 

 Lloyd Morgan kinesis (see our p. "i^oo, footnote) is purely 

 a mode of describing conceptually the sequences of my 

 sense-impressions," then the door would not have been 

 opened for the metaphysician to parody metakinesis by 

 supermateriality. So long as the biologist is taught to 

 look upon mechanism as a series of imperceptible motions 

 undertaken by imperceptible bodies under the guidance of 

 imperceptible " molecular forces," he cannot be criticised 

 for introducing another imperceptible element — " meta- 

 kinesis " — into this process. But when the physicist 

 ceases to postulate any of these imperceptibles and boldly 

 states that mechanism is a conceptual process, by aid of 

 which he is able to describe certain phases at any rate in 

 those sequences of sense-impressions which we classify as 

 unconscious life, then he may fairly ask what sense- 

 impressions of unconscious life the biologist classifies by 

 aid of metakinesis. If the biologist replies it is the 

 potentiality of consciousness, then this is not the equivalent 

 of the mechanism of primitive forms of life. The latter 

 corresponds not only to the potentiality of all the complex 

 nervous system of a conscious organism, but it actually 

 describes some of our perceptual experience of primitive 

 life. It thus does more than describe a potentiality, it 

 describes a reality, and thus cannot be classed like meta- 

 kinesis with supermateriality as a metaphysical " being," 

 " essence," or " aspect." 



The biologist therefore may describe for us the various 



