Mankind always sets itself only such tasks as it can solve; since, looking at the matter more closely, we will always find that the task itself arises only when the material conditions necessary for its solution already exist or are at least in the process of formation.

Last words are for those fools who believe they have not yet said enough.

In the national struggles of the proletarians of the different countries, they point out and bring to the front the common interest of the entire proletariat, independently of all nationality.

Since only what is material is perceptible, knowable, nothing is known of the existence of God.

Labour is ... not the only source of material wealth, i.e, of the use-values it produces. As William Petty says, Labour is the father of material wealth, the earth is its mother.

The abolition of religion as the illusory happiness of the people is the demand for their real happiness. To call on them to give up their illusions about their condition is to call on them to give up a condition that requires illusions. The criticism of religion is, therefore, in embryo, the criticism of that vale of tears of which religion is the halo.

The weapon of criticism can never replace the criticism of weapons.