Of course, Marx, like all the great economists, includes in his concept of labor every kind of productive effort, mental as well as physical, as Mr. Mallock, to the utter destruction of his disingenuous criticism, unconsciously--we must suppose--admitted. Take, for example, this definition: "By labor power or capacity for labor is to be understood the aggregate of those _mental and physical_ capabilities existing in a human being, which he exercises when he produces a use-value of any description."[161] As against this luminous and precise definition, it is but fair to quote that of Mr. Mallock himself. He defines labor as "the faculties of an individual _applied to his own labor_"[162]--a meaningless jumble of words. The fifty-seven letters contained in that sentence would mean just as much if put in a bag, well shaken, and put on paper just as they happened to fall from the bag. Marx never argued that the producers of wealth had a _right_ to the wealth produced. The "right of labor to the whole of its produce" was, it is true, the keynote of the theories of the Ricardian Socialists. An echo of the doctrine appeared in the Gotha Programme of the German Socialists to which reference has already been made, and in the popular agitation of Socialism in this and other countries it is echoed more or less frequently. Just in proportion as the ethical argument for Socialism is advanced, and appeals made to the sense of justice, the rich idler is condemned and an ethic of distribution based upon production becomes an important feature of the propaganda. But Marx nowhere indulges in this kind of argument. Not in a single line of "Capital," or his minor economic treatises, can any hint of the doctrine be found. He invariably scoffed at the "ethical distribution" idea. In the judgment of the present writer, this is at once his great strength and weakness, but that is beside the point of this discussion. Suffice it to say, though it involves some reiteration, that Marx never took the position that Socialism _ought_ to take the place of capitalism, because the producers of wealth _ought_ to get the whole of the wealth they produce. His position was rather that Socialism _must_ come, simply because capitalism _could not_ last.