The values of commodities are directly as the times of labor employed in their production, and are inversely as the productive powers of the labor employed.

The directing motive, the end and aim of capitalist production, is to extract the greatest possible amount of surplus value, and consequently to exploit labor-power to the greatest possible extent.

The merit of painting lies in the exactness of reproduction. Painting is a science and all sciences are based on mathematics. No human enquiry can be a science unless it pursues its path through mathematical exposition and demonstration.

Capitalism is commodity production at the highest stage of development, when labor power itself becomes a commodity. The growth of internal exchange, and particularly of international exchange, is a special feature of capitalism. The uneven and spasmodic character of the development of individual enterprises, of individual branches of industry and individual countries, is inevitable under the capitalist system.

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.

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.