The variety of colour in objects cannot be discerned at a great distance, excepting in those parts which are directly lighted up by the solar rays.

The study of what is excellent is food for the mind and body.

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.

Experience is a truer guide than the words of others.

As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.

Nothing is so much to be feared as Evil Report.

Avoid the precepts of those thinkers whose reasoning is not confirmed by experience.