Karl Marx, Friedrich Engels. The Communist Manifesto (№ 232688)

All the preceding classes that got yourself the upper hand sought to fortify their already acquired status in life, subordinating all of society to their conditions of appropriation. The proletarians cannot become the social productive forces except by abolishing their own previous mode of appropriation, and thereby also every other previous still the mode of appropriation. The proletarians have nothing of their own that would have them protect, they must destroy all that is still guarded and secured private property.