Notices respecting New Boohs. 405 



This leads our author to the discussion of Berkeley's views on 

 this matter ; and he places before us, in a very clear and well- 

 ordered manner, the arguments which led Berkeley to the opinion 

 that the ideas derived from sight have nothing in common with 

 those derived from touch, except that they arise in connexion with 

 one another in an absolutely invariable way ; and that the supposed 

 likeness between the ideas themselves is the result of our lifelong 

 constant experience which has coordinated these essentially hete- 

 rogeneous things. 



But while a priori reasoning such as Berkeley's is interesting, it 

 is a somewhat unsafe guide in matters of Physiology ; for we have 

 no means but experiment by which we can find out whether perhaps 

 these essentially heterogeneous sensations may not be coordinated 

 by unsuspected nervous connexions quite independently of any 

 experience on the part of the individual. And indeed the pheno- 

 mena of innate reflex action, and observations made on the move- 

 ments of the young of many of the lower animals, lead to the 

 opinion that, in some animals at least, the observations of the dif- 

 ferent senses are coordinated to some extent independently of the 

 experience of the individual animal. We might therefore naturally 

 enough suppose that this is a question of degree ; and that man, 

 who takes so long to learn to use his senses, has less of this innate co- 

 ordination than a bird, which can walk and pick up grains almost 

 as soon as it escapes from the shell. 



It is therefore with satisfaction that we turn to the third part of 

 Dr. Loewy's work, the experiments on blind persons who have been 

 made to see. 



The first of these is Cheselden's famous case. Our author 

 gives details of all the cases of similar experiments; and it is 

 surprising to note how little the recent cases, observed with all the 

 modern appliances of science, have added to the information given 

 by Cheselden. The concurrent testimony of all the carefully ob- 

 served cases confirms the view of Molyneux and Berkeley — the 

 blind men made to see did not distinguish the cube from the sphere. 

 The only fact which the new cases have added to our knowledge is 

 that this inability to recognize forms is certainly not due to imper- 

 fection in the transparency of the humours of the eye ; as in some 

 of them careful ophthalmoscopic observations were made, with the 

 result that the optical condition of the eye was found perfect and 

 sharp images were formed on the retina. 



But because visible form or size has no necessary relation to 

 tactual form or size, it does not follow that there is nothing com- 

 mon to the two senses. Indeed there is an idea which seems to be 

 common to all the senses — that is, the idea of duration and succes- 

 sion. Perhaps it is because this seems at first as if it were altogether 

 independent of sensation that it has been overlooked. We are apt 

 to think that it coexists with the various senses, rather than is 

 derived from each or any of them. But leaving out of view this 

 metaphysical question, there can scarcely be a doubt that a blind 

 man made to see would at once recognize a rhythm with which he 



