Again, most of the chief distinctions marked by economic terms are differences not of kind but of degree.

Knowledge is our most powerful engine of production.

Material goods consist of useful material things, and of all rights to hold, or use, or derive benefits from material things, or to receive them at a future time.

And very often the influence exerted on a person's character by the amount of his income is hardly less, if it is less, than that exerted by the way in which it is earned.

Political Economy or Economics is a study of mankind in the ordinary business of life.

Every short statement about economics is misleading (with the possible exception of my present one).

But if inventions have increased man's power over nature very much, then the real value of money is better measured for some purposes in labour than in commodities.