Constant labor of one uniform kind destroys the intensity and flow of a man's animal spirits, which find recreation and delight in mere change of activity.

Accumulation of wealth at one pole is at the same time accumulation of misery, agony of toil, slavery, ignorance, brutality, mental degradation, at the opposite pole

Life is not determined by consciousness, but consciousness by life.

Religion is only the illusory sun which revolves round man as long as he does not revolve round himself.

It has drowned the most heavenly ecstasies of religious fervour, of chivalrous enthusiasm, of Philistine sentimentalism, in the icy water of egotistical calculation. It has resolved personal worth into exchange value, and in place of numberless indefeasible chartered freedoms, it has set up that single, unconscionable freedom -- free trade. In one word, for exploitation, veiled by religious and political illusions, it has substituted naked, shameless, direct, brutal exploitation.

The democratic concept of man is false, because it is Christian. The democratic concept holds that . . . each man is a sovereign being. This is the illusion, dream, and postulate of Christianity.

Darwin's book is very important and serves me as a basis in natural science for the class struggle in history. One has to put up with the crude English method of development, of course. Despite all deficiencies not only is the death-blow dealt here for the first time to 'teleology' in the natural sciences, but their rational meaning is empirically explained.