Eric Wolf on Labor power

“Wealth in the hands of the holders of wealth is not capital until it controls the means of production, buys labor power, and puts it to work, continuously expanding surpluses by intensifying productivity through an ever-rising curve of technological inputs.”

“The capitalist mode acts to accumulate capital through the hiring of labor power, but is marked by the cyclical alternation of labor mobilization and labor displacement; each intake of labor power uproots some prior adaptation, while each sloughing off of labor power creates a new cohort of the unemployed.”

“The essence of capital is its ability to mobilize social labor by buying labor power and setting it to work. This requires a market in which the capacity of human beings to work can be bought and sold like any other commodity: buyers of labor power offer wages, which sellers accept in return for a commodity, their own labor.”

“Only when the stock of wealth can be related to human energy by purchasing living energy as "labor power", offered for sale by people who have no other means of using their labor to ensure their livelihood: and only when it can relate that labor power to purchased machines - embodiments of past transformation of nature by human energy expended in the past - only then does "wealth" become "capital".”