Mechanics is the paradise of the mathematical sciences because by means of it one comes to the fruits of mathematics.

When the thing taken into union is perfectly adapted to that which receives it, the result is delight and pleasure and satisfaction.

If you are alone you belong entirely to yourself. If you are accompanied by even one companion you belong only half to yourself or even less in proportion to the thoughtlessness of his conduct and if you have more than one companion you will fall more deeply into the same plight.

The knowledge of all things is possible

Ask counsel of him who rules himself well.

You should prefer a good scientist without literary abilities than a literate one without scientific skills

Make your faces so that they do not all have the same expression, as one sees with most painters, but give them different expression, according to age, complexion, and good or bad character.