Brad DeLong explains:

Negative supply shocks and missed collective guesses on what the extent of the market will be in the future create overaccumulation and overproduction. Marx is very clear that the monetary crisis theorists–like John Stuart Mill–must be wrong, and that the system cannot run itself without crises.

DeLong notes that Marx takes the opposite view regarding the boom and bust that often occurs in capitalist environments. Either the system ought to be overthrown, or it needs to be born like a great labour because it is inherently good.

Despite the nearly 130 years since Marx’s words, it remains nearly impossible to find a thinker as complex and deep as Marx.