Hitherto men have constantly made up for themselves false conceptions about themselves, about what they are and what they ought to be. They have arranged their relationships according to their ideas of God, of normal man, etc. The phantoms of their brains have got out of their hands. They, the creators, have bowed down before their creations. Let us liberate them from the chimeras, the ideas, dogmas, imaginary beings under the yoke of which they are pining away. Let us revolt against the rule of thoughts. Let us teach men, says one, to exchange these imaginations for thoughts which correspond to the essence of man; says the second, to take up a critical attitude to them; says the third, to knock them out of their heads; and-existing reality will collapse.

- Karl Marx