Do not put forward anything that you cannot prove by experimentation.

Every chemical substance, whether natural or artificial, falls into one of two major categories, according to the spatial characteristic of its form. The distinction is between those substances that have a plane of symmetry and those that do not. The former belong to the mineral, the latter to the living world.

If science has no country, the scientist should have one, and ascribe to it the influence which his works may have in this world.

The Greeks bequeathed to us one of the most beautiful words in our language--the word 'enthusiasm'--en theos--a god within. The grandeur of human actions is measured by the inspiration from which they spring. Happy is he who bears a god within, and who obeys it.

There is no such thing as a special category of science called applied science; there is science and its applications, which are related to one another as the fruit is related to the tree that has borne it.

Blessed is he who carries within himself a God, an ideal, and obeys it.

Life comes only from life.