What is the significance of "the reserve army of the unemployed"? How does the tendency toward oligopoly - what Marx tends to call monopolization - in the capitalist economy lead, according to Marx, to the "proletarianization" of many capitalists, the "tendency of the rate of profit to fall," and, ultimately, a coming "proletarian revolution"? [HINT: Marx in Capital Vol. 3 outlines the theory of surplus-value where the rate of profit has a tendencyto fall]