The country that is more developed industrially only shows, to the less developed, the image of its own future.

Music is the mirror of reality.

Labor, being itself a commodity, is measured as such by the labor time needed to produce the labor-commodity. And what is needed to produce this labor-commodity? Just enough labor time to produce the objects indispensable to the constant maintenance of labor, that is, to keep the worker alive and in a condition to propagate his race. The natural price of labor is no other than the wage minimum.

Religion is the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions. It is the opium of the people.

Advances in science help to delegitimize the rule of kings and the power of the Church.

There is only one effective antidote for mental suffering and that is physical pain.

Under private property, each tries to establish over the other an alien power, so as thereby to find satisfaction of his own selfish need. The increase in the quantity of objects is therefore accompanied by an extension of the realm of the alien powers to which man is subjected, and every new product represents a new potentiality of mutual swindling and mutual plundering.