It is impossible to read the works of the economists who since the time of Smith have endeavored to build up and elucidate the science of political economy without seeing how, over and over again, they stumble over the law of wages without once recognizing it. Yet, "if it were a dog it would bite them!" Indeed, it is difficult to resist the impression that some of them really saw this law of wages, but, fearful of the practical conclusions to which it would lead, preferred to ignore and cover it up, rather than use it as the key to problems which without it are so perplexing. A great truth to an age which has rejected and trampled on it, is not a word of peace, but a sword!

Progress and Poverty (1879)