The claims of justice, narrowly interpreted, may reinforce this tendency. It may be thought unjust that some men should have larger incomes or shorter hours of work than other men. But efficiency in mental work, including the work of education, certainly requires more comfort and longer periods of rest than are required for efficiency in physical work, if only because mental work is not physiologically wholesome. If this is not recognized, the life of the mind may suffer through short-sightedness even more than through deliberate hostility. Education suffers at present, and may long continue to suffer, through the desire of parents that their children should earn money as soon as possible. Every one knows that the half-time system, for example, is bad; but the power of organized labor keeps it in existence. It is clear that the cure for this evil, as for those that are concerned with the population question, is to relieve parents of the expense of their children’s education, and at the same time to take away their right to appropriate their children’s earnings. The way to prevent any dangerous opposition of labor to the life of the mind is not to oppose the labor movement, which is too strong to be opposed with justice. The right way is, to show by actual practice that thought is useful to labor, that without thought its positive aims cannot be achieved, and that there are men in the world of thought who are willing to devote their energies to helping labor in its struggle. Such men, if they are wise and sincere, can prevent labor from becoming destructive of what is living in the intellectual world. Another danger in the aims of organized labor is the danger of conservatism as to methods of production. Improvements of machinery or organization bring great advantages to employers, but involve temporary and sometimes permanent loss to the wage-earners. For this reason, and also from mere instinctive dislike of any change of habits, strong labor organizations are often obstacles to technical progress. The ultimate basis of all social progress must be increased technical efficiency, a greater result from a given amount of labor. If labor were to offer an effective opposition to this kind of progress, it would in the long run paralyze all other progress. The way to overcome the opposition of labor is not by hostility or moral homilies, but by giving to labor the direct interest in economical processes which now belongs to the employers. Here, as elsewhere, the unprogressive part of a movement which is essentially progressive is to be eliminated, not by decrying the whole movement but by giving it a wider sweep, making it more progressive, and leading it to demand an even greater change in the structure of society than any that it had contemplated in its inception.