The great word Evolution had not yet, in 1860, made a new religion of history, but the old religion had preached the same doctrinefor a thousand years without finding in the entire history of Rome anything but flat contradiction.

Absolute liberty is absence of restraint; responsibility is restraint; therefore, the ideally free individual is responsible to himself.

Some day science may have the existence of mankind in its power, and the human race commit suicide, by blowing up the world.

The Jewish question is really the most serious of our problems.

One does every day and without a second thought, what at another time would be the event of a year, perhaps of a life.

After Gibbs, one the most distinguished [American scientists] was Langley, of the Smithsonian. ... He had the physicist's heinous fault of professing to know nothing between flashes of intense perception. ... Rigidly denying himself the amusement of philosophy, which consists chiefly in suggesting unintelligible answers to insoluble problems, and liked to wander past them in a courteous temper, even bowing to them distantly as though recognizing their existence, while doubting their respectibility.

History is the most aristocratic of all literary pursuits, because it obliges the historian to be rich as well as educated.