3. _Increase of efficiency due to the sacrifice of parents or to personal exertion, goes to the individual worker._ The most essential practical feature in any industrial system is the appeal to the ambition of each man. This appeal is made where a premium is placed on increasing efficiency, by insuring to it a higher return. This result is possible and in large measure is attained under the wage system. Little less important is the appeal to family affection to make possible by its sacrifices each worker's best preparation. An offsetting disadvantage appears in the loss to the laborer in the decline of his powers. As he gains in wages if he increases in efficiency, so he loses if his strength fails from accident or in the course of years. This loss falls upon him, not, as is sometimes said to have been the case under serfdom or slavery, upon his owner (as if that secured to the slave immunity from suffering). It is true that in general under the wage system the worker has no guarantee against loss of work or, what is equally important, against sudden changes in industry. He may be, and often is, a victim of invention and of changes in machinery or industrial processes, by which the masses of men are the gainers. [Sidenote: Large liberty of the wage-worker] 4. _Liberty of the worker in his choice of work and outside of working hours makes for happiness, character, and progress._ Opinion is almost a unit as to the truth of this statement. The present wage system is the freest condition for the mass of men that ever has existed. Their religious, political, and personal convictions, are for the most part inviolate. There is a true but much misused maxim that liberty has its dangers. Freedom means freedom to make mistakes. Intelligence and strong industrial virtues are required to exercise properly a freedom newly acquired. Thus it is the lowest class of labor that reaps the smallest advantage from free conditions, and that suffers most from their misuse. [Sidenote: Limits to the worker's liberty]