3, taxes on imports for other than fiscal purposes, is not among this number. Just now such taxes seem to be coming back into fashion, or to be enjoying a certain revival. It is a sign of the deficiency of our sociology as compared with our other sciences that such a phenomenon could be presented in the last quarter of the nineteenth century, as a certain revival of faith in the efficiency of taxes on imports as a device for producing national prosperity. There is not a single one of the eleven devices mentioned above, including taxes on the exportation of machinery and prohibitions on emigration, which is not quite as rational and sound as taxes on imports.
I now propose to analyze and criticize protectionism.
(C) Definition of Protectionism — Definition of "Theory."
7. By protectionism I mean the doctrine of protective taxes as a device to be employed in the art of national prosperity. The protectionists are fond of representing themselves as "practical" and the free traders as "theorists." "Theory" is indeed one of the most abused words in the language, and the scientists are partly to blame for it. They have allowed the word to come into use, even among themselves, for a conjectural explanation, or a speculative conjecture, or a working hypothesis, or a project which has not yet been tested by experiment, or a plausible and harmless theorem about transcendental relations, or about the way in which men will act under certain motives. The newspapers seem often to use the word "theoretical" as if they meant by it imaginary or fictitious. I use the word "theory," however, not in distinction from fact, but, in what I understand to be the correct scientific use of the word, to denote a rational description of a group of coördinated facts in their sequence and relations. A theory may, for a special purpose, describe only certain features of facts and disre-
