This will become evident to any one who will take the trouble, for instance, to examine into the various definitions of life which have been given by philosophers and scientists.(70) Still, they all agree, however widely they may differ in their views concerning what life is in itself, that the law of growth applies to all living beings. This is true, not of physical life alone, but of intellectual and moral life as well. What I have to say on this subject at present relates more especially to intellectual life, which consists in the union of the intelligent principle with the objects submitted to it, and which it apprehends as true—that is, as being in reality what they seem to be, and resulting from this, as good or beautiful. Truth is the harmony of thought with things.(71) Intellectual growth is a continual approach to the perfect harmony of thought with things, which, however, to the finite mind, is unattainable; and this fact constitutes one of the great charms of the cultivation of the mind. The nature of the human intellect places limits to mental progress, though they are not assignable in any given case, but may be indefinitely extended. That there are limits, however, you will readily perceive by reflecting that we do not possess even one idea which does not, either in itself or in its postulates, contain something which transcends all human comprehension. What, let us ask ourselves, is the law of intellectual growth? The condition of all growth is effort. Life is a struggle in which lesser forces are overcome by greater. This is true of the individual as of the race. It is only by effort, by the exertion of power, that we live and consequently grow. Labor, then, is the law of intellectual as of all progress. Before going further, let us examine into the obstacles which tend to prevent improvement of mind. These are to be sought for either in the circumstances which surround us or in ourselves. We are to such an extent the creatures of circumstances that, when these are unfavorable, it is almost impossible that we should make great head‐way. As occasion makes the thief, it is also required to make the scholar. In the first place, leisure is essential to mental culture, since education is a work of time and of labor. We therefore look for little or no cultivation of mind in those who lead lives of manual toil, and who, during the brief moments allowed for recreation, are so fatigued as to be incapable of sustained mental effort. Here and there an individual from this class, of remarkable gifts, and endowed with great energy and will, surmounts the obstacle, and, having risen to a higher level, succeeds, by perseverance and industry, in making very considerable intellectual progress. But, as a rule, all will admit that it would be absurd to look for much mental training in men who work ten or even eight hours a day in factories and mines, or in tilling the soil.