Antoine Lavoisier

Vegetation is the basic instrument the creator uses to set all of nature in motion.

We must clean house thoroughly, for they have made use of an enigmatical language peculiar to themselves, which in general presents one meaning for the adepts and another meaning for the vulgar, and at the same time contains nothing that is rationally true either in the one meaning or the other.

A man cannot imagine things which he has not already perceived by his senses.

The constancy of the composition of the atmosphere is one of the most remarkable phenomena in physics.

It is a principle in physics that in every change there is an equality between the cause and the effect.

The true means of increasing the mass of real knowledge is to neglect no observable fact, to be careful in collecting them, and to be scrupulously exact in verifying them.

In every operation there is an equal quantity of matter before and after the operation.

Caloric is the cause of heat, and of the expansion of bodies; it penetrates all bodies, and dilates them.

The art of drawing conclusions from experiments and observations consists in evaluating probabilities and in judging whether they are sufficiently great or numerous enough to constitute proofs.

The light of experiment and observation is the only light worth following.

I am persuaded that the progress of the human mind will be extremely rapid when it is once freed from the shackles which have been imposed upon it.

The theory of phlogiston has retarded the progress of chemistry like an evil genius.

The moment of greatest enlightenment is the moment of danger.

It is with a method as it is with a language: its perfection consists in its simplicity.

The more one advances in the knowledge of nature, the more difficult it becomes to establish a system that is free from contradictions.

In the arts and sciences, as in nature, everything is linked together.

A well-made experiment is preferable to a badly drawn conclusion.

The habit of reasoning does not destroy the feelings; it permits us to direct them.

To doubt is the first step towards knowledge.

The air which has been rendered noxious by respiration is not only deprived of a part of its vital air, but it also contains a considerable quantity of fixed air (carbon dioxide).