Electricity is of two kinds, positive and negative. The difference is, I presume, that one comes a little more expensive, but is more durable; the other is a cheaper thing, but the moths get into it.

Too much has been said of the heroes of history-the strong men, the troublesome men; too little of the amiable, the kindly, the tolerant.

The student of arithmetic who has mastered the first four rules of his art, and successfully striven with money sums and fractions, finds himself confronted by an unbroken expanse of questions known as problems.

It was Einstein who made the real trouble. He announced in 1905 that there was no such thing as absolute rest. After that there never was.

The writing of solid, instructive stuff fortified by facts and figures is easy enough. There is no trouble in writing a scientific treatise on the folk-lore of Central China, or a statistical enquiry into the declining population of Prince Edward Island. But to write something out of one's own mind, worth reading for its own sake, is an arduous contrivance only to be achieved in fortunate moments, few and far in between. Personally, I would sooner have written Alice in Wonderland than the whole Encyclopedia Britannica.

I am a great believer in luck, and I find the harder I work the more I have of it.

It's called political economy because it is has nothing to do with either politics or economy.