We must expect the discovery of many as yet unknown elements-for example, elements analogous to aluminum and silicon- whose atomic weight would be between 65 and 75.

No law of nature, however general, has been established all at once; its recognition has always been preceded by many presentiments.

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.

The magnitude of the atomic weight determines the character of the element, just as the magnitude of the molecule determines the character of a compound body.

The edifice of science not only requires material, but also a plan. Without the material, the plan alone is but a castle in the air-a mere possibility; whilst the material without a plan is but useless matter.