The acquisition of knowledge is always of use to the intellect, because it may thus drive out useless things and retain the good. For nothing can be … - Leonardo da Vinci

If you transmit the rays of the sun through a hole in the shape of a star you will see a beautiful effect of perspective in the spot where the sun's rays fall.

He makes powerful and very strong wines, … and the wine is worth more than a penny per jug and the pound of veal a penny and the salt 10 denarii, and so is the butter, and their pound is 30 ounces, and the eggs a penny. (referring to the food products of Valtellina)

Tomaso of Florence. known as Masaccio, showed by his perfect works how those who took their nourishment from anything but nature, mistress of masters, were laboring in vain.