Natural science will in time incorporate into itself the science of man, just as the science of man will incorporate into itself natural science: there will be one science.
Karl MarxPolitical economy regards the proletarian like a horse, he must receive enough to enable him to work. It does not consider him, during the time when he is not working, as a human being. It leaves this to criminal law, doctors, religion, statistical tables, politics, and the beadle.
Karl MarxWe know that violent measures against religion are nonsense; but this is an opinion: as socialism grows, religion will disappear. Its disappearance must be done by social development, in which education must play a part.
Karl MarxAll 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.
Karl Marx