There is nothing in this world that I fear to say.

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

When the elements are arranged in vertical columns according to increasing atomic weight, so that the horizontal lines contain analogous elements again according to increasing atomic weight, an arrangement results from which several general conclusions may be drawn.

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

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.

The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties.

Work, look for peace and calm in work: You will find it nowhere else. Pleasures flit by -- they are only for yourself; work leaves a mark of long-lasting joy, work is for others.