Mechanics is the paradise of the mathematical sciences because by means of it one comes to the fruits of mathematics.
Leonardo da VinciThe lover is moved by the thing loved, as the sense is by that which perceives, and it unites with it and they become one and the same thing... when the lover is united with the beloved it finds rest there; when the burden is laid down there it finds rest.
Leonardo da VinciThose who are in love with practice without knowledge are like the sailor who gets into a ship without rudder or compass and who never can be certain whether he is going. Practice must always be founded on sound theory, and to this Perspective is the guide and the gateway; and without this nothing can be done well in the matter of drawing.
Leonardo da Vinci