Whoever despises the high wisdom of mathematics nourishes himself on delusion and will never still the sophistic sciences whose only product is an eternal uproar. Mechanics is the paradise of the mathematical sciences, because by means of it one comes to the fruits of mathematics. Notebooks , v. 1, ch. He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.
Inequality is the cause of all local movements.
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. The function of muscle is to pull and not to push, except in the case of the genitals and the tongue. The sun does not move.