There are, according to Marx, objective contradictions in the unfolding of capitalism. Due to the law of the tendency of the rate of profit to decline there is, over time, a greater reduction in the rate of profit than there is increase in the rate of exploitation. This means that capitalist accumulation proceeds, as a whole, ever slower. This is a strong argument against the internal consistency of the economic system itself. This, we might say, is a strong or objective contradiction. Each individual capitalist’s attempt to increase efficiency and realize higher than average profit rates has the knock-on and accumulated effect of producing declining rates of return as a whole. This of course produces cycles characterized at one end by declining investment and over-accumulation. This in turn is also an underlying reason why capital is unstable and prone to crises. Capital survives not in peaceful, consistent, harmonious accord with the needs of consumers, but in uneven cycles of plenty and self-incurred scarcity. At certain points the greater development of capacities to produce what society certainly needs is itself hampered by the requirement that doing so be in the service of recuperating the rate of profit. In this way, the strong objective contradiction has its correlates in disjuncts between the aims of directors of discrete capitals and the social outcomes of all behaving in a like manner. The logical contradiction can be sharpened, softened, revealed, dulled, and covered by ideology or not, but it and its socially pernicious correlates are always operative.
As Marx repeatedly pointed out, one of the most harmful effects of the grand contradiction is what it does to the workers that make the system run. On one side growing efficiency reduces the cost of supplying what the working class needs (needs can here be understood from the standpoint of the reproduction of their labor-power, and are thus not needs in any robust sense), and on the other side, this efficiency means for the capitalist a reduction in number or compensation of the employed. A mass of un- and precariously employed join the exploited workers among the disadvantaged that keep the contradictory system afloat. In Marxist prognosis and organizational practice the mass is to fight against this abusive logic, and here we can see a transition from what I’ve called the grand contradiction of capital to the social contradictions at its constitutively unquiet basis.