We have by inference already obtained the law of wages. But to verify the deduction and to strip the subject of all ambiguities, let us seek the law from an independent starting point.

There is, of course, no such thing as a common rate of wages, in the sense that there is at any given time and place a common rate of interest. Wages, which include all returns received from labor, not only vary with the differing powers of individuals, but, as the organization of society becomes elaborate, vary largely as between occupations. Nevertheless, there is a certain general relation between all wages, so that we express a clear and well understood idea when we say that wages are higher or lower in one time or place than in another. In their degrees, wages rise and fall in obedience to a common law. What is this law?

The fundamental principle of human action—the law that is to political economy what the law of gravitation is to physics—is that men seek to gratify their desires with the least exertion. Evidently, this principle must bring to an equality, through the competition it induces, the reward gained by equal exertions under similar circumstances. When men work for themselves, this equalization will be largely affected by the equation of prices; and between those who work for themselves and those who work for others, the same tendency to equalization will operate.