Alterius non sit qui suus esse potest. (Let no man belong to another that can belong to himself.)

Consider that we shouldn't call our brother a fool, since we don't know ourselves what we are.

Everything is a drug; it depends on the dose.

Nature is a light, and by looking at Nature in her own light we will understand her. Visible Nature may be seen in her visible light; invisible Nature may become visible if we acquire the power to perceive her invisible light.

And it is true, best is nothing concealed which shall not be discovered; for which cause a marvellous being shall come after me, who as yet lives not, and who shall reveal many things.

He who knows nothing loves nothing. He who can do nothing understands nothing. He who understands nothing is worthless. But he who understands also loves, notices, sees. The more knowledge is inherent in a thing, the greater the love.

Many have said of Alchemy, that it is for the making of gold and silver. For me such is not the aim, but to consider only what virtue and power may lie in medicines.