The human mind evolved always in the company of the human body, and of the animal body before it was human. The intricate connections of mind and body must exceed our imagination, as from our point of view we are peculiarly prevented from observing them.

Religious suffering is at once the expression of real suffering and a protest against real suffering. Religion is the sigh of the oppressed creature, the sentiment of the heartless world, as it is the soul of soulless condition. It is the opium of the people.

It is characteristic of science that the full explanations are often seized in their essence by the percipient scientist long in advance of any possible proof.

The recognition of the art that informs all pure science need not mean the abandonment for it of all present art, rather it will mean the completion of the transformation of art that has already begun.

The relevance of Marxism to science is that it removes it from its imagined position of complete detachment and shows it as a part, but a critically important part, of economy and social development.