"I would give a thousand secrets of nature upon which I stumbled by accident, in exchange for this one which I extracted from nature, in spite of all the miracles and dangers which I faced."

"Everyone should consider his body as a priceless gift from one whom he loves above all, a marvelous work of art, of indescribable beauty, and mystery beyond human conception, and so delicate that a wo…"

"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more."

"I myself have made my own discoveries in the greatest solitude, and when I have been alone, undisturbed."

"I could only achieve success in my life through self-discipline, and I applied it until my wish and my will became one."