THE MIND-STUFF THEORY. 169 



sory perce23ts which have been explained to result from 

 unconscious logic operations. 



Reply. That chapter will also in many cases refute 

 this explanation. Color- and light-contrast are certainly 

 purely sensational afiairs, in which inference plays no part. 

 This has been satisfactorily proved by Hering,* and shall 

 be treated of again in Chapter XYII. Our rapid judg- 

 ments of size, shape, distance, and the like, are best ex- 

 plained as processes li" simple cerebral association. Cer- 

 tain sense-impressions directly stimulate brain-tracts, of 

 whose activity ready-made conscious percepts are the 

 immediate psychic counterparts. They do this by a mech- 

 anism either connate or acquired by habit. It is to be 

 remarked that Wundt and Helmholtz, who in their earlier 

 writings did more than any one to give vogue to the notion 

 that unconscious inference is a vital factor in sense-percep- 

 tion, have seen fit on later occasions to modify their views 

 and to admit that results like those of reasoning ma}- accrue 

 without any actual reasoning process unconsciously taking 

 place. t Maybe the excessive and riotous applications made 

 by Hartmann of their principle have led them to this 

 change. It would be natural to feel towards him as the 

 sailor in the story felt towards the horse who got his foot 

 into the stirrup, — " If you're going to get on, I must get ofi." 



Hartmann fairly boxes the compass of the universe with 

 the principle of unconscious thought. For him there is no 

 namable thing that does not exemj^lify it. But his logic 

 is so lax and his failure to consider the most ob\'ious alter- 

 natives so complete that it would, on the whole, be a 

 waste of time to look at his arguments in detail. The same 

 is true of Schopenhauer, in whom the mythology reaches 

 its climax. The visual perception, for example, of an 

 object in space results, according to him, from the intellect 

 l^erforming the following operations, all unconscious. First, 

 it apprehends the inverted retinal image and turns it right 

 side up, constructing _y?«^ space as a preliminary operation ; 



* Zur Lehre vom Lichtsiune (187SK 



f Cf. ^¥u^dt: Ueher den Einttuss der Philosopbie, etc. — Antrittsrede 

 tl876), pp. 10-11; — Helmholtz: Die Thulsacheu in der Wabrnebniuug, 

 1879), p. 27. 



