Some speculative physicians seem to have imagined that the health of the human body could be preserved only by a certain precise regimen of diet and exercise, of which every, the smallest, violation necessarily occasioned some degree of disease or disorder proportioned to the degree of the violation. Experience, however, would seem to show that the human body frequently preserves, to all appearances at least, the most perfect state of health under a vast variety of different regimens; even under some which are generally believed to be very far from being perfectly wholesome. But the healthful state of the human body, it would seem, contains in itself some unknown principle of preservation, capable either of preventing or of correcting, in many respects, the bad effects even of a very faulty regimen. Mr. Quesnai, who was himself a physician, and a very speculative physician, seems to have entertained a notion of the same kind concerning the political body, and to have imagined that it would thrive and prosper only under a certain precise regimen, the exact regimen of perfect liberty and perfect justice. He seems not to have considered that, in the political body, the natural effort which every man is continually making to better his own condition is a principle of preservation capable of preventing and correcting, in many respects, the bad effects of a political economy, in some degree, both partial and oppressive. Such a political economy, though it no doubt retards more or less, is not always capable of stopping altogether the natural progress of a nation towards wealth and prosperity, and still less of making it go backwards. If a nation could not prosper without the enjoyment of perfect liberty and perfect justice, there is not in the world a nation which could ever have prospered. In the political body, however, the wisdom of nature has fortunately made ample provision for remedying many of the bad effects of the folly and injustice of man, in the same manner as it has done in the natural body for remedying those of his sloth and intemperance.

The capital error of this system, however, seems to lie in its representing the class of artificers, manufacturers, and merchants as altogether barren and unproductive. The following observations may serve to show the impropriety of this representation.

First, this class, it is acknowledged, reproduces annually the value of its own annual consumption, and continues, at least, the existence of the stock or capital which maintains and employs it. But upon this account alone the denomination of barren or unproductive should seem to be very improperly applied to it. We should not call a marriage barren or unproductive though it produced only a son and a daughter, to replace the father and mother, and though it did not increase the number of the human species, but only continued it as it was before. Farmers and country labourers, indeed, over and above the stock which maintains and employs them, reproduce annually a net produce, a free rent to the landlord. As a marriage which affords three children is certainly more productive than one which affords only two; so the labour of farmers and country labourers is certainly more productive than that of merchants, artificers, and manufacturers. The superior produce of the one class, however, does not render the other barren or unproductive.

Secondly, it seems, upon this account, altogether improper to consider artificers, manufacturers, and merchants in the same light as menial servants. The labour of menial servants does not continue the existence of the fund which maintains and employs them. Their maintenance and employment is altogether at the expense of their masters, and the work which they perform is not of a nature to repay that expense. That work consists in services which perish generally in the very instant of their performance, and does not fix or realize itself in any vendible commodity which can replace the value of their wages and maintenance. The labour, on the contrary, of artificers, manufacturers, and merchants naturally does fix and realize itself in some such vendible commodity. It is upon this account that, in the chapter in which I treat of productive and unproductive labour, I have classed artificers, manufacturers, and merchants among the productive labourers, and menial servants among the barren or unproductive.

Thirdly, it seems upon every supposition improper to say that the labour of artificers, manufacturers, and merchants does not increase the real revenue of the society. Though we should suppose, for example, as it seems to be supposed in this system, that the value of the daily, monthly, and yearly consumption of this class was exactly equal to that of its daily, monthly, and yearly production, yet it would not from thence follow that its labour added nothing to the real revenue, to the real value of the annual produce of the land and labour of the society. An artificer, for example, who, in the first six months after harvest, executes ten pounds' worth of work, though he should in the same time consume ten pounds' worth of corn and other necessaries, yet really adds the value of ten pounds to the annual produce of the land and labour of the society. While he has been consuming a half-yearly revenue of ten pounds' worth of corn and other necessaries, he has produced an equal value of work capable of purchasing, either to himself or some other person, an equal half-yearly revenue. The value, therefore, of what has been consumed and produced during these six months is equal, not to ten, but to twenty pounds. It is possible, indeed, that no more than ten pounds' worth of this value may ever have existed at any one moment of time. But if the ten pounds' worth of corn and other necessaties, which were consumed by the artificer, had been consumed by a soldier or by a menial servant, the value of that part of the annual produce which existed at the end of the six months would have been ten pounds less than it actually is in consequence of the labour of the artificer. Though the value of what the artificer produces, therefore, should not at any one moment of time be supposed greater than the value he consumes, yet at every moment of time the actually existing value of goods in the market is, in consequence of what he produces, greater than it otherwise would be.

When the patrons of this system assert that the consumption of artificers, manufacturers, and merchants is equal to the value of what they produce, they probably mean no more than that their revenue, or the fund destined for their consumption, is equal to it. But if they had expressed themselves more accurately, and only asserted that the revenue of this class was equal to the value of what they produced, it might readily have occurred to the reader that what would naturally be saved out of this revenue must necessarily increase more or less the real wealth of the society. In order, therefore, to make out something like an argument, it was necessary that they should express themselves as they have done; and this argument, even supposing things actually were as it seems to presume them to be, turns out to be a very inconclusive one.

Fourthly, farmers and country labourers can no more augment, without parsimony, the real revenue, the annual produce of the land and labour of their society, than artificers, manufacturers, and merchants. The annual produce of the land and labour of any society can be augmented only in two ways; either, first, by some improvement in the productive powers of the useful labour actually maintained within it; or, secondly, by some increase in the quantity of that labour.

The improvement in the productive powers of useful labour depend, first, upon the improvement in the ability of the workman; and, secondly, upon that of the machinery with which he works. But the labour of artificers and manufacturers, as it is capable of being more subdivided, and the labour of each workman reduced to a greater simplicity of operation than that of farmers and country labourers, so it is likewise capable of both these sorts of improvements in a much higher degree. In this respect, therefore, the class of cultivators can have no sort of advantage over that of artificers and manufacturers.

The increase in the quantity of useful labour actually employed within any society must depend altogether upon the increase of the capital which employs it; and the increase of that capital again must be exactly equal to the amount of the savings from the revenue, either of the particular persons who manage and direct the employment of that capital, or of some other persons who lend it to them. If merchants, artificers, and manufacturers are, as this system seems to suppose, naturally more inclined to parsimony and saving than proprietors and cultivators, they are, so far, more likely to augment the quantity of useful labour employed within their society, and consequently to increase its real revenue, the annual produce of its land and labour.

Fifthly and lastly, though the revenue of the inhabitants of every country was supposed to consist altogether, as this system seems to suppose, in the quantity of subsistence which their industry could procure to them; yet, even upon this supposition, the revenue of a trading and manufacturing country must, other things being equal, always be much greater than that of one without trade or manufactures. By means of trade and manufactures, a greater quantity of subsistence can be annually imported into a particular country than what its own lands, in the actual state of their cultivation, could afford. The inhabitants of a town, though they frequently possess no lands of their own, yet draw to themselves by their industry such a quantity of the rude produce of the lands of other people as supplies them, not only with the materials of their work, but with the fund of their subsistence. What a town always is with regard to the country in its neighbourhood, one independent state or country may frequently be with regard to other independent states or countries. It is thus that Holland draws a great part of its subsistence from other countries; live cattle from Holstein and Jutland, and corn from almost all the different countries of Europe. A small quantity of manufactured produce purchases a great quantity of rude produce. A trading and manufacturing country, therefore, naturally purchases with a small part of its manufactured produce a great part of the rude produce of other countries; while, on the contrary, a country without trade and manufactures is generally obliged to purchase, at the expense of a great part of its rude produce, a very small part of the manufactured produce of other countries. The one exports what can subsist and accommodate but a very few, and imports the subsistence and accommodation of a great number. The other exports the accommodation and subsistence of a great number, and imports that of a very few only. The inhabitants of the one must always enjoy a much greater quantity of subsistence than what their own lands, in the actual state of their cultivation, could afford. The inhabitants of the other must always enjoy a much smaller quantity.

This system, however, with all its imperfections is, perhaps, the nearest approximation to the truth that has yet been published upon the subject of political economy, and is upon that account well worth the consideration of every man who wishes to examine with attention the principles of that very important science. Though in representing the labour which is employed upon land as the only productive labour, the notions which it inculcates are perhaps too narrow and confined; yet in representing the wealth of nations as consisting, not in the unconsumable riches of money, but in the consumable goods annually reproduced by the labour of the society, and in representing perfect liberty as the only effectual expedient for rendering this annual reproduction the greatest possible, its doctrine seems to be in every respect as just as it is generous and liberal. Its followers are very numerous; and as men are fond of paradoxes, and of appearing to understand what surpasses the comprehension of ordinary people, the paradox which it maintains, concerning the unproductive nature of manufacturing labour, has not perhaps contributed a little to increase the number of its admirers. They have for some years past made a pretty considerable sect, distinguished in the French republic of letters by the name of The Economists. Their works have certainly been of some service to their country; not only by bringing into general discussion many subjects which had never been well examined before, but by influencing in some measure the public administration in favour of agriculture. It has been in consequence of their representations, accordingly, that the agriculture of France has been delivered from several of the oppressions which it before laboured under. The term during which such a lease can be granted, as will be valid against every future purchaser or proprietor of the land, has been prolonged from nine to twenty-seven years. The ancient provincial restraints upon the transportation of corn from one province of the kingdom to another have been entirely taken away, and the liberty of exporting it to all foreign countries has been established as the common law of the kingdom in all ordinary cases. This sect, in their works, which are very numerous, and which treat not only of what is properly called Political Economy, or of the nature and causes of the wealth of nations, but of every other branch of the system of civil government, all follow implicitly and without any sensible variation, the doctrine of Mr. Quesnai. There is upon this account little variety in the greater part of their works. The most distinct and best connected account of this doctrine is to be found in a little book written by Mr. Mercier de la Riviere, some time intendant of Martinico, entitled, The Natural and Essential Order of Political Societies. The admiration of this whole sect for their master, who was himself a man of the greatest modesty and simplicity, is not inferior to that of any of the ancient philosophers for the founders of their respective systems. "There have been, since the world began," says a very diligent and respectable author, the Marquis de Mirabeau, "three great inventions which have principally given stability to political societies, independent of many other inventions which have enriched and adorned them. The first is the invention of writing, which alone gives human nature the power of transmitting, without alteration, its laws, its contracts, its annals, and its discoveries. The second is the invention of money, which binds together all the relations between civilised societies. The third is the Economical Table, the result of the other two, which completes them both by perfecting their object; the great discovery of our age, but of which our posterity will reap the benefit."

As the political economy of the nations of modern Europe has been more favourable to manufactures and foreign trade, the industry of the towns, than to agriculture, the industry of the country; so that of other nations has followed a different plan, and has been more favourable to agriculture than to manufactures and foreign trade.

The policy of China favours agriculture more than all other employments. In China the condition of a labourer is said to be as much superior to that of an artificer as in most parts of Europe that of an artificer is to that of a labourer. In China, the great ambition of every man is to get possession of some little bit of land, either in property or in lease; and leases are there said to be granted upon very moderate terms, and to be sufficiently secured to the lessees. The Chinese have little respect for foreign trade. Your beggarly commerce! was the language in which the Mandarins of Pekin used to talk to Mr. de Lange, the Russian envoy, concerning it. Except with Japan, the Chinese carry on, themselves, and in their own bottoms, little or no foreign trade; and it is only into one or two ports of their kingdom that they even admit the ships of foreign nations. Foreign trade therefore is, in China, every way confined within a much narrower circle than that to which it would naturally extend itself, if more freedom was allowed to it, either in their own ships, or in those of foreign nations.