Although in any sociological inquiry these two methods are equally valid, or, more strictly speaking, are equally balanced in virtues and defects, the latter method is here to be preferred, because by the order of its descent from the whole to the constituent parts it brings out more definitely the slight cohesiveness and integration of industry beyond the national limits, and serves to emphasise those qualities of nationalism and narrow localism which mark the character of earlier eighteenth century industry. We are thus enabled better to recognise the nature and scope of the work wrought by the modern industrial forces which are the central object of study.
While the Market or the Trade is less and less determined or confined by national or other political boundaries in modern times, and nationalism is therefore a factor of diminishing importance in the modern science of economics, the paramount domination of politics over large commerce in the last century, acting in co-operation with other racial and national forces, obliges any just analysis of eighteenth century industry to give clear and early emphasis to the slight character of the commercial interdependency among nations. The degree of importance which statesmen and economists attached to this foreign commerce as compared with home trade, and the large part it played in the discussion and determination of public conduct, have given it a prominence in written history far beyond its real value.[3]
It is true that through the Middle Ages a succession of European nations rose to eminence by the development of navigation and international trade, Italy, Portugal, Spain, France, Holland, and England; but neither in size nor in character was this trade of the first importance. Even in the case of those nations where it was most developed it formed a very small proportion of the total industry of the country, and it was chiefly confined to spicery, bullion, ornamental cloths, and other objects of art and luxury.
It is important to recognise that in the first half of the eighteenth century international trade still largely partook of this character. Not only did it bear a far smaller proportion to the total industry of the several countries than does foreign trade to-day, but it was still engaged to a comparatively small extent with the transport of necessaries or prime conveniences of life. Each nation, as regards the more important constituents of its consumption, its staple foods, articles of clothing, household furniture, and the chief implements of industry, was almost self-sufficing, producing little that it did not consume, consuming little it did not produce.