The more necessary a thing is for living beings, the more easily it is found and the cheaper it is; the less necessary it is, the rarer and dearer it is.

At times the truth shines so brilliantly that we perceive it as clear as day. Our nature and habit then draw a veil over our perception, and we return to a darkness almost as dense as before. We are like those who, though beholding frequent flashes of lightning, still find themselves in the thickest darkness of the night.

Let nothing which can be treated by diet be treated by other means.

The more we desire for that which is superfluous, the more we meet with difficulties; our strength and possessions are spent in unnecessary things, and are wanting when required for that which is necessary.

The goal of good health is to enable a person to acquire wisdom.

In the realm of Nature there is nothing purposeless, trivial, or unnecessary

Do not imagine that what we have said of the insufficiency of our understanding and of its limited extent is an assertion founded only on the Bible: for philosophers likewise assert the same, and perfectly understand it,- without having regard to any religion or opinion.