Antoine Lavoisier

I die as I have lived, a servant of science and a victim of the French Revolution.

We must trust to nothing but facts: these are presented to us by nature and cannot deceive.

It took them only an instant to cut off that head, but France may not produce another like it in a century.

The art of concluding from experience and observation consists in evaluating probabilities.

I have lived long enough to be certain that the world will not be ready for my discoveries until at least a hundred years after my death.

We may lay it down as an incontestible axiom, that, in all the operations of art and nature, nothing is created; an equal quantity of matter exists both before and after the experiment; the quality and quantity of the elements remain precisely the same; and nothing takes place beyond changes and modifications in the combination of these elements.

As ideas are preserved and communicated by means of words, it necessarily follows that we cannot improve the language of any science, without at the same time improving the science itself; neither can we, on the other hand, improve a science without improving the language or nomenclature which belongs to it.

Here, then: a revolution [in science and chemistry] has taken place in an important part of human knowledge since your departure from Europe… I will consider this revolution to be well advanced and even completely accomplished if you range yourself with us. …After having brought you up to date on what is happening in chemistry, it would be well to speak to you about our political revolution. We regard it as done and without any possibility of return to the old order.

Imagination, on the contrary, which is ever wandering beyond the bounds of truth, joined to self-love and that self-confidence we are so apt to indulge, prompt us to draw conclusions which are not immediately derived from facts.

The success of charlatans, sorcerors, and alchemists—and all those who abuse public credulity—is founded on errors in this type of calculation.

Nothing is created, either in the operations of art, or in those of nature; and it may be considered as a general principle that in every operation there exists an equal quantity of matter before and after the operation.

It is almost possible to predict one or two days in advance, within a rather broad range of probability, what the weather is going to be; it is even thought that it will not be impossible to publish daily forecasts, which would be very useful to society.

Languages are true analytical methods; algebra, which is adapted to its purpose in every species of expression, in the most simple, most exact, and best manner possible, is at the same time a language and an analytical method.

The art of concluding from experience and observation consists in evaluating probabilities, in estimating if they are high or numerous enough to constitute proof.

It is not often that a man has the opportunity to be useful to his fellow citizens without any personal risk.

I consider nature a vast chemical laboratory, in which all sorts of combinations and decompositions are continually taking place.

Nothing is lost, nothing is created, everything is transformed.

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

It is impossible for me to write anything without feeling myself inspired by a sort of scientific enthusiasm.

I have been so lucky in life, that I have had nothing to do but to collect the fruits of the labours of others.