ON THE PSYCHO-PHYSICAL VIEW OF NATURE. 499 



led psychologists to consider more closely the conditions 

 under which a mathematical treatment is at all possible, 

 and to recognise that exact and accurate measurements 

 must precede all application of an abstract calculus. 

 Herbart's ideal was that of a psychical mechanics ; he 

 opposed l the idea of a union of physiology and 

 psychology. And yet this was just the direction in 



1 In a very interesting note at 

 the end of the introduction to the 

 second part of his larger work on 

 psychology, Herbart explains his 

 position with regard to physiological 

 psychology. It refers to certain 

 extracts which he makes from 

 Rudolph's ' Grundriss der Physiol- 

 ogic,' in which that eminent physi- 

 ologist referred to Herbart's ' Lehr- 

 buch der Psychologic. ' " It is not 

 only a metaphysical but also a 

 logical error to confound psycho- 

 logical and physiological research. 

 Psychological phenomena are not 

 in space, but space itself, with all 

 that appears in it, is a psycholog- 

 ical phenomenon, and, indeed, one 

 of the first and most difficult facts 

 for psychology, which, in the treat- 

 ment of it, would behave very im- 

 properly if it began by discussing 

 the forces in the nerves ; for the 

 question is not, where sensations 

 come from, but how sensations 

 acquire the form of space. Now, I 

 maintain further, that the differ- 

 ence between lifeless and living 

 matter that is, between physics 

 and physiology cannot be under- 

 stood until we know mind by means 

 of psychology, for in all the count- 

 less elements of the organised body 

 in plants as well as in animals 

 there is an analogue of mental de- 

 velopment which cannot possibly 

 be found on the surface of phen- 

 omena. We observe internally a 

 fragment of our own mental exist- 

 ence. This fragment is developed 

 into scientific knowledge through 



speculative psychology based on 

 metaphysics. This knowledge 

 meets another equally metaphy- 

 sical science, natural philosophy, 

 with its conception of matter 

 that is, of such matter as we know 

 through chemistry and dynamics. 

 Then only can the question be put, 

 how such matter must be con- 

 stituted, so that its separate ele- 

 ments are determined, not only 

 through their original quality, but 

 also through a development analo- 

 gous to the mental one," &c. The 

 section closes with the following 

 characteristic passage : " Those 

 who favour empiricism can learn 

 from the present state of physi- 

 ology how much, or rather how 

 little, mere experience can do. 

 Physiology, as an empirical doc- 

 trine, has attained a height which 

 nobody can despise. Moreover, it 

 proceeds in the light of modern 

 physics. Nevertheless, it has 

 eagerly sucked up, as the sponge 

 sucks up water, that philosophy 

 of nature which knows nothing, 

 because it began by construing the 

 universe a priori. Towards this 

 error no science has proved so 

 weak, so little capable of resist- 

 ance, as physiology. The talk 

 about life has become the Dead 

 Sea in which all spirit of philo- 

 sophical research is drowned, so 

 that, if a resurrection is at all to 

 be hoped for, it must be born anew 

 in quite unbiassed minds" ('Werke,' 

 vol. vi. p. 65, &c. ) 



