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

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.

The more fodder, the more flesh; the more flesh, the more manure; the more manure, the more grain.

Receiving a new truth is like adding a new sense.

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.

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.

I would... establish the conviction that Chemistry, as an independent science, offers one of the most powerful means towards the attainment of a higher mental cultivation; that the study of Chemistry is profitable, not only inasmuch as it promotes the material interests of mankind, but also because it furnishes us with insight into those wonders of creation which immediately surround us, and with which our existence, life, and development, are most closely connected.