I have learnt that all our theories are not Truth itself, but resting places or stages on the way to the conquest of Truth, and that we must be contented to have obtained for the strivers after Truth such a resting place which, if it is on a mountain, permits us to view the provinces already won and those still to be conquered.

I have spent some months in England, have seen an awful lot and learned little. England is not a land of science, there is only a widely practised dilettantism, the chemists are ashamed to call themselves chemists because the pharmacists, who are despised, have assumed this name.

Observation is like a piece of glass, which, as a mirror, must be very smooth, and must be very carefully polished, in order that it may reflect the image pure and undistorted.

We may fairly judge of the commercial prosperity of a country from the amount of sulphuric acid it consumes.

The progress of mankind is due exclusively to the progress of natural sciences, not to morals, religion or philosophy.

The loveliest theories are being overthrown by these damned experiments; it's no fun being a chemist anymore.

A fact acquires its true and full value only through the idea which is developed from it.