Doctrine once sown strikes deep its root, and respect for antiquity influences all men.

Moderate labor of the body conduces to the preservation of health, and cares many initial diseases.

I have often wondered and even laughed at those who fancied that everything had been so consummately and absolutely investigated by an Aristotle or a Galen or some other mighty name, that nothing could by any possibility be added to their knowledge.

As art is a habit with reference to things to be done, so is science a habit in respect to things to be known.

And so I conclude that blood lives and is nourished of itself and in no way depends on any other part of the body as being prior to it or more excellent... So that from this we may perceive the causes not only of life in general... but also of longer or shorter life, of sleeping and waking, of skill, of strength and so forth.

The heart is the household divinity which, discharging its function, nourishes, cherishes, quickens the whole body, and is indeed the foundation of life, the source of all action.

Nature is a volume of which God is the author.