Dmitri Mendeleev — "Hypotheses help and guide scientific work — the search for truth — as the tiller…"

"There exists everywhere a medium in things, determined by equilibrium."

"By gradually studying matter, people finally take command of it."

"I saw in a dream a table where all the elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper, only in one place did a correction later seem necessary."

"There is nothing in science that cannot be explained to a barmaid."

"Experiment itself cannot give truth, but it gives the means of destroying erroneous representations whilst confirming those which are true in all their consequences."