The alienation of man thus appeared as the fundamental evil of capitalist society.

Reason has always existed, but not always in a reasonable form.

All freed, fast-frozen relations, with their train of ancient and venerable prejudices and opinions, are swept away, all new-formed ones become antiquated before they can ossify. All that is solid melts into air, all that is holy is profaned, and man is at last compelled to face with sober senses, his real conditions of life, and his relations with his kind.

The ruling ideas of each age have ever been the ideas of its ruling class.

All history is nothing but a continuous transformation of human nature.

The rule of the bourgeois democrats [in pre-federal Germany], from the very first, will carry within it the seeds of its own destruction

Men make their own history, but they do not make it just as they please; they do not make it under circumstances chosen by themselves, but under circumstances directly encountered, given and transmitted from the past. The tradition of all the dead generations weighs like a nightmare on the brain of the living.