"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."

"It was clear that in the United States there was a development not of the best, but of the middle and worst sides of European civilization; the notorious general voting, the tendency to politics... al…"

"The periodic law is the most important generalization in chemistry, and it has no equal in any other branch of science."

"It is useful in this sense to make a clear distinction between the conception of an element as a separate homogenous substance and as a material but invisible part of a compound."

"I have been called a charlatan, a madman, and a dreamer, but I have always pursued the truth."