Lazy rascals, spending their substance, and more, in riotous living

Who are the lumpen­proletariat?

The concept of the lumpenproletariat is generally used to support a workerist (in the bad sense) form of Marxism, in which the working class’s revolutionary activity comes from their role as producers, and hence the lumpenproletariat, the unproductive poor, have little or no part to play in revolution. The lumpenproletariat then are criminals, prostitutes, the homeless, written off by so-called Marxists along lines very similar to bourgeois discussions of the “underclass.” Aside from the reactionary political implications of this definition, it also seems wrong from a Marxological point of view. In the Manifesto, Marx’s discusses the lumpenproletariat in the context of reactionary groups that attempt to preserve their position within a pre-capitalist order, describing them as:

The “dangerous classes,” the social scum, that passiveley rotting mass thrown off by the lowest layers of old society.

The last part of the definition seems interesting here: the lumpenproletariat are not those excluded from participation in capitalism, but remnants of “old society.” This doesn’t seem to include those included in capitalism in the most precarious or criminalized forms; indeed, I’m not sure who in contemporary society this definition of the lumpenproletariat would apply to. So, who are the lumpenproletariat?