ABSTRACT
(p. 411) The three sources of the economy referred to above: agriculture, industry and trade, cannot result in production without human labour. It is human beings who cultivate the land, manufacture the merchandise and operate the equipment. It is human beings who carry out sales and purchases and they are, therefore, an important source of wealth. Even though human labour is indispensable in agriculture, it is certainly not considered part of it. As with industry and trade, human labour is not considered part of any of these three activities as it is a source independent from these three sources.
