Pleasures flit by - they are only for yourself; work leaves a mark of long-lasting joy, work is for others.

Work, look for peace and calm in work: you will find it nowhere else.

The most all penetrating spirit before which will open the possibility of tilting not tables, but planets, is the spirit of free human inquiry. Believe only in that.

Certain characteristic properties of elements can be foretold from their atomic weights.

It is the function of science to discover the existence of a general reign of order in nature and to find the causes governing this order. And this refers in equal measure to the relations of man - social and political - and to the entire universe as a whole.

We could live at the present day without a Plato, but a double number of Newtons is required to discover the secrets of nature, and to bring life into harmony with the laws of nature.