The Protestant Ethic and the Spirit of Capitalismis a series of essays, written by Max Weber in 1905, studying the relationship between religious ideas, in this case Protestantism, and the economic theory of capitalism.

In these essays Weber defines the spirit of capitalism as the rational pursuit of economic gain. Economic gain was the desired end result of devoting one's life to labor. The key though is to profit in the most efficient means necessary. Thus, Weber writes, "Remember that time is money. He that can earn ten shillings a day by his labor, and goes abroad, or sits idle, one half of that day, though he spends but sixpence during his diversion or idleness, ought not to reckon that the only expense; he has really spent, or rather thrown away, five shillings beside" (Weber, 1958: 47).