Country in general, but more particularly to the territories of his Majesty of Great Britain, and his neighbours of Holland, Zealand, and France." This book was presented in manuscript to King Charles II., but was not printed till the year 1690. Lord Shelborne, the author's son, in his dedication of it, observes, "that it was styled by his father Political Arithmetic, inasmuch as things of Government, and of no less concern and extent, than the glory of the Prince, and the happiness and greatness of the People, are by the ordinary rules of arithmetic, brought into a sort of demonstration. He was allowed by all," it is added, "to be the inventor of this method of instruction, where the perplexed and intricate ways of the world are explained by a very mean part of science." On the same subject, Sir William Petty himself writes as follows:—“ The method I take is not very usual; for, instead of giving only comparative and superlative words and intellectual argument, I have taken the course (as a specimen of the Political Arithmetic I have aimed at) to express myself in terms of number, weight, or measure, to use only argument of sense, and to consider only such causes as have visible foundations in nature; leaving those that depend on the mutable minds, opinions, appetites, and passions of particular men to the consideration of others. . . . . Now, the observations or positions expressed by number, weight, and measure, upon which I bottom the ensuing discourses, are either true, or not apparently false; and which, if they are not already true, certain, and evident, yet may be made so by the sovereign power, (nam id certum est quod certum reddi potest;) and if they are false, not so false as to destroy the argument they are brought for, but at worst are sufficient as suppositions, to show the way to that knowledge I aim at. . . . Which, if it shall be judged material and worthy of a better discussion, I hope all ingenious and candid persons will rectify the errors and imperfections which may probably be found in any of the positions on which my ratiocinations are grounded. Nor would it misbecome authority itself, to clear those matters which private endeavours cannot reach to."1 1 Preface to Political Arithmetic. I have quoted these passages at greater length than I should otherwise have thought necessary, in order to show, with how little reason the German writers value themselves as the authors of that science to which they have given the name of Statistics. "It is now about forty years ago," says Zimmermann in his Political Survey of Europe, "that a branch of political knowledge, which has for its object the actual and relative power of the several modern states, the power arising from their natural advantages, the industry and civilisation of their inhabitants, and the wisdom of their governments, has been formed, chiefly by German writers, into a separate science. It used formerly to be improperly connected with geography; and it was but superficially treated amidst the topographical and descriptive details of the larger geographical works. By the more convenient form it has received, and by its growing importance, this science, distinguished by the new-coined name of Statistics, is become a favourite study in Germany."1 The Baron de Hertzberg informs us, in one of his Academical Discourses, that since the middle of the present century it has been gradually supplanting among his countrymen, what used formerly to be the principal object of attention, in the German system of academical education, the system of Natural Jurisprudence. With respect to Sir William Petty, however, whatever his merits were in opening this new field of political research, it must be owned, that in the execution of the plan, he did little more than set an example to his successors. His object was to compute the number of the people from the trade and consumption of the nation, and from the number of houses in the kingdom. For the former branch of information he trusted to the accounts of the Excise and the Customs, and for the latter to the gross produce of the hearth-money. But on none of these articles did he possess the means of ascertaining the truth; 1 Sinclair's Account of the Origin and Progress of the Board of Agriculture, (p. 34.) [Denina, in his Prusse Litté raire, vindicates, as I recollect, the in vention of this branch of science to Italy and to his countryman Botero, who lived long before Petty.] and, accordingly, his computations often proceed on erroneous or uncertain data. His most valuable reasonings are founded on the bills of mortality and the registers of births, which he appears to have studied with great care, with a view to the population both of this and of other countries. A spirit of theory, however, runs through all his speculations, calculated to flatter the wishes and prejudices of government; and hence his anxiety to overrate the resources of England, and to undervalue those of our neighbours. It is thus only we can account for such assertions as the following:-"That France exceeded Great Britain very little in point of territory; that our numbers approach near to those of the French, and, in point of strength, are as efficient; that France was under a natural and perpetual incapacity of being powerful at sea; and that it had not above fifteen thousand seamen to manage its trade, out of which not above ten thousand could be spared for a fleet of war." "Every good Englishman," says Postlethwayt, "does undoubtedly wish all this had been true; but we have since had manifest proofs that this great genius was mistaken in all these assertions, for which reason we have ground to suspect, he rather made his court than spoke his mind." Researches similar to those which Sir William Petty had recommended and exemplified, were afterwards prosecuted (about the end of last century) by Mr. Gregory King, whose results are to this day much valued for their accuracy; and by Dr. Davenant," the best," (according to Dr. Price,) "while not venal, of all political writers."2 The greatest step, however, that has ever been made in this branch of science, by any one individual, was undoubtedly by the original and inventive genius of Dr. Halley, whose observations (of which I shall afterwards have occasion to take notice) have not only contributed much to correct the ideas of political writers on the subject now under our consideration, but have led the way to all the improvements which have since been made in the doctrine of annuities,-a doctrine which forms the 2 Price, On Annuities, Vol. II. p. 1 Postlethwayt's Dictionary; Article, Political Arithmetic. 275. basis of an immense branch of commercial speculation in this country, and which proceeds on one of the most refined general principles that have yet been applied successfully to human affairs, the possibility of counteracting the inconveniences resulting from the precarious duration of life in the case of individuals, by the uniformity of those general laws by which those events that appear the most accidental on a superficial view, are found to be regulated in the order of nature. Among the different methods which have been employed for estimating the state of population, one of the most simple is founded on the supposed proportion between the number of houses and that of the inhabitants. In order, however, to employ this method with advantage, in particular instances, much attention is necessary to the circumstances of the case. The proportion between the number of houses and that of their inhabitants must vary widely, it is evident, according to the opulence or poverty of the people; according to their habits of living; according to their residence in towns or in the country; according to the size of towns, their commercial or dissipated manners, and many other accidents. The calculations of Gregory King on this subject are founded on an examination of the hearth-books, and of the assessments on marriages, births, and burials, and (in the opinion of Dr. Davenant) "are more to be relied on than anything of the same kind that had ever been attempted." According to these calculations, London within the walls produced almost The rest of the bills of mortality, almost 5 per house. 42 41 4층 Upon the whole, (making allowance for divided houses, occupied by different families, for uninhabited houses, &c.,) he was led to conclude, that in England and Wales the people answer to four and a half per house and four per family.1 1 Chalmers's Estimate, pp. 54, 56. Subsequent inquirers have enumerated the houses and the inhabitants of various villages, towns, and cities, instead of relying on the defective returns of tax-gatherers; and from their researches it appears, that King's estimates of the number of dwellers which he allowed to every house, and to every family, were considerably under the truth. From a table published by Dr. Price in his Treatise on Annuities, containing the results of actual surveys of the number of inhabitants, houses, and families in many different places, that ingenious writer was led to conclude, "That six to a house was probably too large an allowance for London, and that five to a house was certainly an allowance sufficiently large for England in general." The same Table (although not quite so complete) is inserted in Morgan's Doctrine of Annuities and Assurances. Mr. Howlett, [Examination, &c.] from a still more extensive series of observations, insists for five and twofifths, which, in the opinion of Mr. Chalmers, we may reasonably conclude to be the smallest number which dwells in every house, on an average of the whole kingdom.2 M. Moheau, in his Researches concerning the Population of France, (published in 1778,) allows only five inhabitants to a house, on a general average of the population, both in towns and in the country. Another principle from which conclusions have sometimes been deduced on the subject of population, is the quantity of consumption in the article of food. Supposing the mean consumption of individuals in bread-corn to be known, and also the annual produce of the national territory, with the imports and the exports, the population of the State would of consequence be determined; or, vice versa, the mean consumption might be ascertained on converting the hypothesis. The quantity of wheat, in like manner, imported into a town during a year, compared with the mean annual consumption of an individual, would determine the population of the town, and, in the opinion of a very competent judge, M. Paucton, would afford one of the nearest approximations to the truth that can be obtained in an inquiry of this nature.3 1 Vol. I. p. 247. 2 Estimate, p. 57. 3 Métrologie, [1780,] p. 507. |