'What is prudence in the conduct of every private family,' says Adam Smith,
'can scarce be folly in that of a great kingdom.' Every individual in pursuing his own interests necessarily promotes thereby also the interests of the community. It is evident that every individual, inasmuch as he knows his own local circumstances best and pays most attention to his occupation, is far better able to judge than the statesman or legislator how his capital can most profitably be invested. He who would venture to give advice to the people how to invest their capital would not merely take upon himself a useless task, but would also assume to himself an authority which belongs solely to the producer, and which can be entrusted to those persons least of all who consider themselves equal to so difficult a task. Adam Smith concludes from this: 'Restrictions on trade imposed on the behalf of the internal industry of a country, are mere folly; every nation, like
every individual, ought to buy articles where they can be procured the cheapest; in order to attain to the highest degree of national prosperity, we have simply to follow the maxim of letting things alone (laisser faire et laisser aller).' Smith and Say compare a nation which seeks to promote its industry by protective duties, to a tailor who wants to make his own boots, and to a bootmaker who would impose a toll on those who enter his door, in order to promote his prosperity. As in all errors of the popular school, so also in this one does Thomas Cooper go to extremes in his book
which is directed against the American system of protection. 'Political economy,' he alleges, 'is almost synonymous with the private economy of all individuals;
politics are no essential ingredient of
political economy; it is folly to suppose that the community is something quite different from the individuals of whom it is composed. Every individual knows best how to invest his labour and his capital. The wealth of the community is nothing else than the aggregate of the wealth of all its individual members; and if every individual can provide best for himself, that nation must be the richest in which every individual is most left to himself.' The adherents of the American system of protection had opposed themselves to this argument, which had formerly been adduced by importing merchants in favour of free trade; the American navigation laws had greatly increased the carrying trade, the foreign commerce, and fisheries of the United States; and for the mere protection of their mercantile marine millions had been annually expended on their fleet; according to his theory those laws and this expense also would be as reprehensible as protective duties. 'In any case,' exclaims Mr. Cooper, 'no commerce by sea is worth a naval war; the merchants may be left to protect themselves.'