Faced with the prospect of revolt from the proletariat, the liberal state created a new class: the permanent underclass. Whereas proletarian man was connected to society only as a factor of production, underclass man is not even a factor of production. If proletarian man is like an ox, underclass man is like a rat or pigeon: living a separate existence on the fringes of human society, collecting whatever scraps and refuse come his way. But he serves a purpose: he is the canary in the coal mine for the worker. “Not happy working 40 hours a week in a repetitive, stressful factory job for a barely adequate wage? You better keep showing up for work, or you could wind up in that housing project you drive past in the morning, with your kids getting beat up on the way to school every week.” UPDATE: And of course, Marx saw that liberal reforms would serve to prop-up liberal society, not to genuinely reform it.