4 ON THE AFFINITIES OF THE BRAIN 



there was, according to these writers, actually no difference at all. 

 ' Le cerveau est absolument de la meme forme et de la meme pro- 

 portion V And the doctrine of the immateriality of the soul was, 

 in the estimation of these authors, not merely compatible with, but 

 a corollary of these not wholly correct anatomical premises. Though 

 the brain in each is the same — in the one the power of thought 

 exists, in the other it is absent. Thought, therefore, cannot be a 

 product of the material organism. 'II ne pense pas— y-a-t'il une 

 preuve plus evidente que la matiere seule, quoique parfaitement 

 organisee, ne peut produire, ni la pensee, ni la parole qui en est la 

 signe, a moins qu'elle ne soit anime*e par un principe superieur?' 



The modern idealist may avoid his predecessors' anatomical errors, 

 but if he be true to his principles, he will feel no anxiety to repudiate 

 their metaphysics. He may make his strong position yet stronger, 

 we believe, by adducing biological evidence in disproof of the 

 usually granted assumption, that mental capacity stands always in 

 a certain relation to cerebral development ; but holding, as he does, 

 the existence of an essential difference between mind and matter, 

 he makes himself but a materialist for the nonce, if he express any 

 repugnance to such statements as those just quoted on account of 

 any conclusions to which they could lead Mm. For even if they 

 were wholly, as we believe they are nearly, true to the facts, he 

 could draw from them, if he remained true to his principles, no 

 other conclusions than did Buffon and Tyson. 



Reasoners of the kind to which we allude will do well to imitate 

 the logical consistency of the materialistic author of the ' Icones 

 Cerebri Simiarum.' Tiedemann, at all events, had no half-hearted 

 faith in his creed. He plights his faith to the scalpel and callipers, 

 and betrays no anxiety as to any possible upsetting of his conclusion 

 by such data as consciousness or the history of psychical phenomena 

 could furnish. 'Parvus ergo encephalus orang-utangi rationem 

 physicam et certam prodit, uti jam celeberrimus Soemmerring mo- 

 nuit, cur animi facultatibus tantopere ab homine distet. In homine 

 praevalere cerebrum, summumque hominis bonum, rationis usum, 

 ab ipsa maxima encephali evolutione pendere, haud dubitari potest. 

 Praecipua et essentialis ergo differentia, quae ipsum hominem et 

 reliqua animantia intercedit, in cerebro posita est V 



1 'Histoire Naturelle,' torn. xiv. p. 61, Paris, 1766. 



2 ' Icones/ Cor. xxxii. p. 55. 



