Mi ntal nist-iplim- in I'.itucatwn. 411 



tain than that in future, mind is to be studied in con; 

 lion with the organism by which it is conditioned: when 

 we begin to deal with the problem of mental discipline, 

 metaphysics no longer avail ; it is the organism with which 

 we have finally to deal. 



When it is said that the brain is the organ of the mind, 

 it is meant that in thinking, remembering, reasoning, the 

 brain acts. It is now admitted that all impressions made 

 upon the brain, and all actions occurring within it, are ac- 

 companied by physical changes. Thought usually goes on 

 so quietly, and seems so far removed from bodily activity, 

 that we are easily betrayed into the notion that it is car- 

 ried on in a region of pure spirit ; but this is far from being 

 the truth. The changes of states of consciousness, the 

 course of thought, and all processes of the understanding, 

 are carried on by a constant succession of nerve excite- 

 ments and nerve discharges. The brain is not a chaos of 

 parts thrown together at random; it consists of hundreds 

 of millions of cells and fibres, organized into symmetrical 

 order, so as to produce innumerable connections, crossings, 

 and junctions of exquisite delicacy. The simple elements 

 of mind are built up into complex knowledge by the law 

 of association of ideas ; and the mental associations are 

 formed by combinations of currents in the brain, and are 

 made permanent by the growth and modification of cells 

 at the points of union. When a child associates the sight, 

 weight, and ring of a dollar, with the written word and 

 verbal sound that represent it so firmly together in its 

 mind that any one of these sensations will instantly bring 

 up the others, it is said to " learn " it. But the real fact of 

 the case is, that the currents formed by visible impressions, 

 vocal movements and sounds, are often repeated together, 

 and are thus combined in the brain, and fixed by specific 

 growths at their points of union, and in this way the men- 

 tal associations are cemented by cerebral nutrition. And 



