forces of the system, and the share of these available for brain-work, but other circumstances have to be taken into the account, and I do not enter upon the question here.
There are many details in the economy of the plastic power that have a physical as well as a mental aspect. Such are those relating to the strain and remission of the attention, to the pauses and alternations during the times of drill, to the moderating of the nervous excitement, and other matters. These should all find a place under the head of the Retentive function. It is expedient now to take up the consideration of the subject from the purely mental side.
2. The one circumstance that sums up all the mental aids to plasticity is Concentration. A certain expenditure of nervous power is involved in every adhesion, every act of impressing the memory, every communicated bias; and the more the better. This supposes, however, that we should withdraw the forces, for the time, from every other competing exercise; and, especially, that we should redeem all wasting expenditure for the purpose in view.
It is requisite, therefore, that the circumstances leading to the concentration of the mind should be well understood. We assume that there is power available for the occasion, and we seek to turn it into the proper channel. Now, there is no doubt that the will is the chief intervening influence, and the chief stimulants of the will are, as we know, pleasure and pain. This is the rough view of the case. A little more precision is attainable through our psychological knowledge.
And first, the will itself as an operating or directing power, that is to say, the moving of the organs in a given way under a motive, is a growth or culture; it is very imperfect at first, and improves by usage. A child of twelve months cannot by any inducement be prompted readily to clap its hands, to point with its forefinger, to touch the tip of its nose, to move its left shoulder forward. The most elementary acts of the will, the alphabet of all the higher acquisitions, have first to be learned in a way of their own; and until they have attained a sufficient advancement, so as to be amenable to the spur of a motive, the teacher has nothing to go upon.
I have elsewhere described this early process, as I conceive it, in giving an account of the development of the will. In the practice of education, it is a matter of importance as showing at what time mechanical instruction is possible, and what impedes its progress at the outset, notwithstanding the abundance of plasticity in the brain itself. The disciplining of the organs to follow directions would seem to be the proper province of the infant school.
Coming now to the influences of concentration, we assign the first place to intrinsic charm, or pleasure in the act itself. The law of the will, in its side of greatest potency, is that pleasure sustains the movement that brings it. The whole force of the mind at the moment
