This it was which Mr. Buckle disbelieved. The economy which prevailed throughout nature, he thought it very unlikely should admit of this exception. He considered that human beings acted necessarily from the impulse of outward circumstances upon their mental and bodily condition at any given moment. Every man, he said, acted from a motive; and his conduct was determined by the motive which affected him most powerfully. Every man naturally desires what he supposes to be good for him; but to do well, he must know well. He will eat poison, so long as he does not know that it is poison. Let him see that it will kill him, and he will not touch it. The question was not of moral right and wrong. Once let him be thoroughly made to feel that the thing is destructive, and he will leave it alone by the law of his nature. His virtues are the result of knowledge; his faults, the necessary consequence of the want of it. A boy desires to draw. He knows nothing about it: he draws men like trees or houses, with their centre of gravity anywhere. He makes mistakes, because he knows no better. We do not blame him. Till he is better taught he cannot help it. But his instruction begins. He arrives at straight lines; then at solids; then at curves. He learns perspective, and light and shade. He observes more accurately the forms which he wishes to represent. He perceives effects, and he perceives the means by which they are produced. He has learned what to do; and, in part, he has learned how to do it. His after-progress will depend on the amount of force which his nature possesses; but all this is as natural as the growth of an acorn. You do not preach to the acorn that it is its duty to become a large tree; you do not preach to the art-pupil that it is his duty to become a Holbein. You plant your acorn in favourable soil, where it can have light and air, and be sheltered from the wind; you remove the superfluous branches, you train the strength into the leading shoots. The acorn will then become as fine a tree as it has vital force to become. The difference between men and other things is only in the largeness and variety of man's capacities; and in this special capacity, that he alone has the power of observing the circumstances favourable to his own growth, and can apply them for himself. Yet, again, with this condition,--that he is not, as is commonly supposed, free to choose whether he will make use of these appliances or not. When he knows what is good for him, he will choose it; and he will judge what is good for him by the circumstances which have made him what he is.