First study the science, and then practice the art which is born of that science.

He who can copy can do.

Where there is most feeling, there is the greatest martyrdom.

Patience serves as a protection against wrongs as clothes do against cold.

A clever man without wisdom is like a beautiful flower without fragrance.

Those who become enamoured of the art, without having previously applied to the diligent study of the scientific part of it, may be compared to mariners who put to the sea in a ship without rudder or compass and therefore cannot be certain of arriving at the wished for port.

Nature is so delightful and abundant in its variations that among trees of the same kind there would not be found one which nearly resembles another, and not only the plants as a whole, but among their branches, leaves, and fruit, will not be found one which is precisely like another.