Why did not somebody teach me the constellations, and make me at home in the starry heavens, which are always overhead, and which I don't half know to this day?

The suffering man ought really to consume his own smoke; there is no good in emitting smoke till you have made it into fire.

Philosophy dwells aloft in the Temple of Science, the divinity of its inmost shrine; her dictates descend among men, but she herself descends not : whoso would behold her must climb with long and laborious effort, nay, still linger in the forecourt, till manifold trial have proved him worthy of admission into the interior solemnities.

There can be no acting or doing of any kind till it be recognized that there is a thing to be done; the thing once recognized, doing in a thousand shapes becomes possible.

With respect to duels, indeed, I have my own ideas. Few things in this so surprising world strike me with more surprise. Two little visual spectra of men, hovering with insecure enough cohesion in the midst of the unfathomable, and to dissolve therein, at any rate, very soon, make pause at the distance of twelve paces asunder; whirl around, and simultaneously by the cunningest mechanism, explode one another into dissolution; and, offhand, become air, and non-extant--the little spitfires!

Old age is not a matter for sorrow. It is matter for thanks if we have left our work done behind us.

A force as of madness in the hands of reason has done all that was ever done in the world.