Principles of Political Economy with some of their Applications to Social Philosophy
By John Stuart Mill
John Stuart Mill (1806-1873) originally wrote the
Principles of Political Economy, with some of their Applications to Social Philosophy very quickly, having studied economics under the rigorous tutelage of his father, James, since his youth. It was published in 1848 (London: John W. Parker, West Strand) and was republished with changes and updates a total of seven times in Mill’s lifetime.The edition presented here is that prepared by W. J. Ashley in 1909, based on Mill’s 7th edition, 1870. Ashley followed the 7th edition with great care, noting changes in the editions in footnotes and in occasional square brackets within the text. The text provides English translations to several lengthy quotations originally quoted by Mill in French. Ashley selected these from an 1865 “People’s Edition” of the Principles, but left in those quotations that had been omitted in that edition. He also prepared a useful Bibliographical Appendix, with additional readings and excerpts from some of Mill’s later writings, which we also include in this Econlib Edition. More on Mill’s life and works, as well as details of Ashley’s procedure, can be found in his Introduction.A few corrections of obvious typos were made for this website edition. However, because the original edition was so internally consistent and carefully proofread, we have erred on the side of caution, allowing some typos to remain lest someone doing academic research wishes to follow up. We have changed small caps to full caps for ease of using search engines.Internal references by page numbers have been replaced by linked paragraph reference numbers appropriate for this online edition. Paragraph references typically have three parts: the book, chapter, and paragraph. E.g.,
I.XI.15 refers to Book I, Chapter XI, paragraph 15.
William J. Ashley, ed.
First Pub. Date
London; Longmans, Green and Co.
The text of this edition is in the public domain. Picture of John Stuart Mill courtesy of The Warren J. Samuels Portrait Collection at Duke University.
- Preliminary Remarks
- Bibliographical Appendix
Book II, Chapter XVI
§1. The requisites of production being labour, capital, and natural agents; the only person, besides the labourer and the capitalist, whose consent is necessary to production, and who can claim a share of the produce as the price of that consent, is the person who, by the arrangements of society, possesses exclusive power over some natural agent. The land is the principal of the natural agents which are capable of being appropriated, and the consideration paid for its use is called rent. Landed proprietors are the only class, of any number or importance, who have a claim to a share in the distribution of the produce, through their ownership of something which neither they nor any one else have produced. If there be any other cases of a similar nature, they will be easily understood, when the nature and laws of rent are comprehended.
It is at once evident, that rent is the effect of a monopoly; though the monopoly is a natural one, which may be regulated, which may even be held as a trust for the community generally, but which cannot be prevented from existing. The reason why landowners are able to require rent for their land, is that it is a commodity which many want, and which no one can obtain but from them. If all the land of the country belonged to one person, he could fix the rent at his pleasure. The whole people would be dependent on his will for the necessaries of life, and he might make what conditions he chose. This is the actual state of things in those Oriental kingdoms in which the land is considered the property of the state. Rent is then confounded with taxation, and the despot may exact the utmost which the unfortunate cultivators have to give. Indeed, the exclusive possessor of the land of a country could not well be other than despot of it. The effect would be much the same if the land belonged to so few people, that they could, and did, act together as one man, and fix the rent by agreement among themselves. This case, however, is nowhere known to exist: and the only remaining supposition is that of free competition; the landowners being supposed to be, as in fact they are, too numerous to combine.
§2. A thing which is limited in quantity, even though its possessors do not act in concert, is still a monopolized article. But even when monopolized, a thing which is the gift of nature, and requires no labour or outlay as the condition of its existence, will, if there be competition among the holders of it, command a price, only if it exists in less quantity than the demand. If the whole land of a country were required for cultivation, all of it might yield a rent. But in no country of any extent do the wants of the population require that all the land, which is capable of cultivation, should be cultivated. The food and other agricultural produce which the people need, and which they are willing and able to pay for at a price which remunerates the grower, may always be obtained without cultivating all the land; sometimes without cultivating more than a small part of it; the lands most easily cultivated being preferred in a very early stage of society;
*104 the most fertile, or those in the most convenient situations, in a more advanced state. There is always, therefore, some land which cannot, in existing circumstances, pay any rent; and no land ever pays rent, unless, in point of fertility or situation, it belongs to those superior kinds which exist in less quantity than the demand—which cannot be made to yield all the produce required for the community, unless on terms still less advantageous than the resort to less favoured soils.
There is land, such as the deserts of Arabia, which will yield nothing to any amount of labour; and there is land, like some of our hard sandy heaths, which would produce something, but, in the present state of the soil, not enough to defray the expenses of production. Such lands, unless by some application of chemistry to agriculture still remaining to be invented, cannot be cultivated for profit, unless some one actually creates a soil, by spreading new ingredients over the surface, or mixing them with the existing materials. If ingredients fitted for this purpose exist in the subsoil, or close at hand, the improvement even of the most unpromising spots may answer as a speculation: but if those ingredients are costly, and must be brought from a distance, it will seldom answer to do this for the sake of profit, though the “magic of property” will sometimes effect it. Land which cannot possibly yield a profit, is sometimes cultivated at a loss, the cultivators having their wants partially supplied from other sources; as in the case of paupers, and some monasteries or charitable institutions, among which may be reckoned the Poor Colonies of Belgium. The worse land which can be cultivated as a means of subsistence, is that which will just replace the seed, and the food of the labourers employed on it, together with what Dr. Chalmers calls their secondaries; that is, the labourers required for supplying them with tools, and with the remaining necessaries of life. Whether any given land is capable of doing more than this, is not a question of political economy, but of physical fact. The supposition leaves nothing for profits, nor anything for the labourers except necessaries: the land, therefore, can only be cultivated by the labourers themselves, or else at a pecuniary loss: and
à fortiori, cannot in any contingency afford a rent. The worst land which can be cultivated as an investment for capital, is that which, after replacing the seed, not only feeds the agricultural labourers and their secondaries, but affords them the current rate of wages, which may extend to much more than mere necessaries; and leaves for those who have advanced the wages of these two classes of labourers, a surplus equal to the profit they could have expected from any other employment of their capital. Whether any given land can do more than this, is not merely a physical question, but depends partly on the market value of agricultural produce. What the land can do for the labourers and for the capitalist, beyond feeding all whom it directly or indirectly employs, of course depends upon what the remainder of the produce can be sold for. The higher the market value of produce, the lower are the soils to which cultivation can descend, consistently with affording to the capital employed, the ordinary rate of profit.
As, however, differences of fertility slide into one another by insensible gradations; and differences of accessibility, that is, of distance from markets, do the same; and since there is land so barren that it could not pay for its cultivation at any price; it is evident that, whatever the price may be, there must in any extensive region be some land which at that price will just pay the wages of the cultivators, and yield to the capital employed the ordinary profit, and no more. Until, therefore, the price rises higher, or until some improvement raises that particular land to a higher place in the scale of fertility, it cannot pay any rent. It is evident, however, that the community needs the produce of this quality of land; since if the lands more fertile or better situated than it, could have sufficed to supply the wants of society, the price would not have risen so high as to render its cultivation profitable. This land, therefore, will be cultivated; and we may lay it down as a principle that so long as any of the land of a country which is fit for cultivation, and not withheld from it by legal or other factitious obstacles, is not cultivated, the worst land in actual cultivation (in point of fertility and situation together) pays no rent.
§3. If, then, of the land in cultivation, the part which yields least return to the labour and capital employed on it gives only the ordinary profit of capital, without leaving anything for rent; a standard is afforded for estimating the amount of rent which will be yielded by all other land. Any land yields just as much more than the ordinary profits of stock, as it yields more than what is returned by the worst land in cultivation. The surplus is what the farmer can afford to pay as rent to the landlord; and since, if he did not so pay it, he would receive more than the ordinary rate of profit, the competition of other capitalists, that competition which equalizes the profits of different capitals, will enable the landlord to appropriate it. The rent, therefore, which any land will yield, is the excess of its produce beyond what would be returned to the same capital if employed on the worst land in cultivation. This is not, and never was pretended to be, the limit of metayer rents, or of cottier rents; but it is the limit of farmers’ rents. No land rented to a capitalist farmer will permanently yield more than this; and when it yields less, it is because the landlord foregoes a part of what, if he chose, he could obtain.
This is the theory of rent, first propounded at the end of the last century by Dr. Anderson, and which, neglected at the time, was almost simultaneously rediscovered, twenty years later, by Sir Edward West, Mr. Malthus, and Mr. Ricardo. It is one of the cardinal doctrines of political economy; and until it was understood, no consistent explanation could be given of many of the more complicated industrial phenomena. The evidence of its truth will be manifested with a great increase of clearness, when we come to trace the laws of the phenomena of Value and Price. Until that is done, it is not possible to free the doctrine from every difficulty which may present itself, nor perhaps to convey, to those previously unacquainted with the subject, more than a general apprehension of the reasoning by which the theorem is arrived at. Some, however, of the objections commonly made to it, admit of a complete answer even in the present stage of our inquiries.
It has been denied that there can be any land in cultivation which pays no rent; because landlords (it is contended) would not allow their land to be occupied without payment. Those who lay any stress on this as an objection, must think that land of the quality which can but just pay for its cultivation, lies together in large masses, detached from any land of better quality. If an estate consisted wholly of this land, or of this and still worse, it is likely enough that the owner would not give the use of it for nothing; he would probably (if a rich man) prefer keeping it for other purposes, as for exercise, or ornament, or perhaps as a game preserve. No farmer could afford to offer him anything for it, for purposes of culture; though something would probably be obtained for the use of its natural pasture, or other spontaneous produce. Even such land, however, would not necessarily remain uncultivated. It might be farmed by the proprietor; no unfrequent case even in England. Portions of it might be granted as temporary allotments to labouring families, either from philanthropic motives, or to save the poor-rate; or occupation might be allowed to squatters, free of rent, in the hope that their labour might give it value at some future period. Both these cases are of quite ordinary occurrence. So that even if an estate were wholly composed of the worst land capable of profitable cultivation, it would not necessarily lie uncultivated because it could pay no rent. Inferior land, however, does not usually occupy, without interruption, many square miles of ground; it is dispersed here and there, with patches of better land intermixed, and the same person who rents the better land, obtains along with it inferior soils which alternate with it. He pays a rent, nominally for the whole farm, but calculated on the produce of these parts alone (however small a portion of the whole) which are capable of returning more than the common rate of profit. It is thus scientifically true, that the remaining parts pay no rent.
§4. Let us, however, suppose that there were a validity in this objection, which can by no means be conceded to it; that when the demand of the community had forced up food to such a price as would remunerate the expense of producing it from a certain quality of soil, it happened nevertheless that all the soil of that quality was withheld from cultivation, by the obstinacy of the owners in demanding a rent for it, not nominal, nor trifling, but sufficiently onerous to be a material item in the calculations of a farmer. What would then happen? Merely that the increase of produce, which the wants of society required, would for the time be obtained wholly (as it always is partially), not by an extension of cultivation, but by an increased application of labour and capital to land already cultivated.
Now we have already seen that this increased application of capital, other things being unaltered, is always attended with a smaller proportional return. We are not to suppose some new agricultural invention made precisely at this juncture; nor a sudden extension of agricultural skill and knowledge, bringing into more general practice, just then, inventions already in partial use. We are to suppose no change, except a demand for more corn, and a consequent rise of its price. The rise of price enables measures to be taken for increasing the produce, which could not have been taken with profit at the previous price. The farmer uses more expensive manures; or manures land which he formerly left to nature; or procures lime or marl from a distance, as a dressing for the soil; or pulverizes or weeds it more thoroughly; or drains, irrigates, or subsoils portions of it, which at former prices would not have paid the cost of the operation; and so forth. These things, or some of them, are done, when, more food being wanted, cultivation has no means of expanding itself upon new lands. And when the impulse is given to extract an increased amount of produce from the soil, the farmer or improver will only consider whether the outlay he makes for the purpose will be returned to him with the ordinary profit, and not whether any surplus will remain for rent. Even, therefore, if it were the fact, that there is never any
land taken into cultivation, for which rent, and that too of an amount worth taking into consideration, was not paid; it would be true, nevertheless, that there is always some
agricultural capital which pays no rent, because it returns nothing beyond the ordinary rate of profit: this capital being the portion of capital last applied—that to which the last addition to the produce was due: or (to express the essentials of the case in one phrase), that which is applied in the least favourable circumstances. But the same amount of demand, and the same price, which enable this least productive portion of capital barely to replace itself with the ordinary profit, enable every other portion to yield a surplus proportioned to the advantage it possesses. And this surplus it is, which competition enables the landlord to appropriate. The rent of all land is measured by the excess of the return to the whole capital employed on it, above what is necessary to replace the capital with the ordinary rate of profit, or in other words, above what the same capital would yield if it were all employed in as disadvantageous circumstances as the least productive portion of it; whether that least productive portion of capital is rendered so by being employed on the worst soil, or by being expended in extorting more produce from land which already yielded as much as it could be made to part with on easier terms.
It is not pretended that the facts of any concrete case conform with absolute precision to this or any other scientific principle. We must never forget that the truths of political economy are truths only in the rough: they have the certainty, but not the precision, of exact science.
*105 It is not, for example, strictly true that a farmer will cultivate no land, and apply no capital, which returns less than the ordinary profit. He will expect the ordinary profit on the bulk of his capital. But when he has cast in his lot with his farm, and bartered his skill and exertions, once for all, against what the farm will yield to him, he will probably be willing to expend capital on it (for an immediate return) in any manner which will afford him a surplus profit, however small, beyond the value of the risk, and the interest which he must pay for the capital if borrowed, or can get for it elsewhere if it is his own. But a new farmer, entering on the land, would make his calculations differently, and would not commence unless he could expect the full rate of ordinary profit on all the capital which he intended embarking in the enterprise. Again, prices may range higher or lower during the currency of a lease, than was expected when the contract was made, and the land, therefore, may be over or under-rented: and even when the lease expires, the landlord may be unwilling to grant a necessary diminution of rent, and the farmer, rather than relinquish his occupation, or seek a farm elsewhere when all are occupied, may consent to go on paying too high a rent. Irregularities like these we must always expect; it is impossible in political economy to obtain general theorems embracing the complications of circumstances which may affect the result in an individual case. When, too,
*106 the farmer class, having but little capital, cultivate for subsistence rather than for profit, and do not think of quitting their farm while they are able to live by it, their rents approximate to the character of cottier rents, and may be forced up by competition (if the number of competitors exceeds the number of farms) beyond the amount which will leave to the farmer the ordinary rate of profit. The laws which we are enabled to lay down respecting rents, profits, wages, prices, are only true in so far as the persons concerned are free from the influence of any other motives than those arising from the general circumstances of the case, and are guided, as to those, by the ordinary mercantile estimate of profit and loss. Applying this twofold supposition to the case of farmers and landlords, it will be true that the farmer requires the ordinary rate of profit on the whole of his capital; that whatever it returns to him beyond this he is obliged to pay to the landlord, but will not consent to pay more; that there is a portion of capital applied to agriculture in such circumstances of productiveness as to yield only the ordinary profits; and that the difference between the produce of this, and any other capital of similar amount, is the measure of the tribute which that other capital can and will pay, under the name of rent, to the landlord. This constitutes a law of rent, as near the truth as such a law can possibly be: though of course modified or disturbed in individual cases, by pending contracts, individual miscalculations, the influence of habit, and even the particular feelings and dispositions of the persons concerned.
§5. A remark is often made, which must not here be omitted, though, I think, more importance has been attached to it than it merits. Under the name of rent, many payments are commonly included which are not a remuneration for the original powers of the land itself, but for capital expended on it. The additional rent which land yields in consequence of this outlay of capital, should, in the opinion of some writers, be regarded as profit, not rent. But before this can be admitted, a distinction must be made. The annual payment by a tenant almost always includes a consideration for the use of the buildings on the farm; not only barns, stables, and other outhouses, but a house to live in, not to speak of fences and the like. The landlord will ask, and the tenant give, for these, whatever is considered sufficient to yield the ordinary profit, or rather (risk and trouble being here out of the question) the ordinary interest, on the value of the buildings: that is, not on what it has cost to erect them, but on what it would now cost to erect others as good: the tenant being bound, in addition, to leave them in as good repair as he found them, for otherwise a much larger payment than simple interest would of course be required from him. These buildings are as distinct a thing from the farm as the stock or the timber on it; and what is paid for them can no more be called rent of land, than a payment for cattle would be, if it were the custom that the landlord should stock the farm for the tenant. The buildings, like the cattle, are not land, but capital, regularly consumed and reproduced; and all payments made in consideration for them are properly interest.
But with regard to capital actually sunk in improvements, and not requiring periodical renewal, but spent once for all in giving the land a permanent increase of productiveness, it appears to me that the return made to such capital loses altogether the character of profits, and is governed by the principles of rent. It is true that a landlord will not expend capital in improving his estate, unless he expects from the improvement an increase of income surpassing the interest of his outlay. Prospectively, this increase of income may be regarded as profit; but when the expense has been incurred, and the improvement made, the rent of the improved land is governed by the same rules as that of the unimproved. Equally fertile land commands an equal rent, whether its fertility is natural or acquired; and I cannot think that the incomes of those who own the Bedford Level or the Lincolnshire Wolds ought to be called profit and not rent because those lands would have been worth next to nothing unless capital had been expended on them. The owners are not capitalists, but landlords; they have parted with their capital; it is consumed, destroyed; and neither is, nor is to be, returned to them, like the capital of a farmer or manufacturer, from what it produces. In lieu of it they now have land of a certain richness, which yields the same rent, and by the operation of the same causes, as if it had possessed from the beginning the degree of fertility which has been artificially given to it.
Some writers, in particular Mr. H. C. Carey, take away, still more completely than I have attempted to do, the distinction between these two sources of rent, by rejecting one of them altogether, and considering all rent as the effect of capital expended. In proof of this, Mr. Carey contends that the whole pecuniary value of all the land in any country, in England for instance, or in the United States, does not amount to anything approaching to the sum which has been laid out, or which it would even now be necessary to lay out, in order to bring the country to its present condition from a state of primæval forest. This startling statement has been seized on by M. Bastiat
*107 and others, as a means of making out a stronger case than could otherwise be made in defence of property in land. Mr. Carey’s proposition, in its most obvious meaning, is equivalent to saying, that if there were suddenly added to the lands of England an unreclaimed territory of equal natural fertility, it would not be worth the while of the inhabitants of England to reclaim it: because the profits of the operation would not be equal to the ordinary interest on the capital expended. To which assertion if any answer could be supposed to be required, it would suffice to remark, that land not of equal but of greatly inferior quality to that previously cultivated, is continually reclaimed in England, at an expense which the subsequently accruing rent is sufficient to replace completely in a small number of years. The doctrine, moreover, is totally opposed to Mr. Carey’s own economical opinions. No one maintains more strenuously than Mr. Carey the undoubted truth, that as society advances in population, wealth, and combination of labour, land constantly rises in value and price. This, however, could not possibly be true, if the present value of land were less than the expense of clearing it and making it fit for cultivation; for it must have been worth this immediately after it was cleared; and according to Mr. Carey it has been rising in value ever since.
When, however, Mr. Carey asserts that the whole land of any country is not now worth the capital which has been expended on it, he does not mean that each particular estate is worth less than what has been laid out in improving it, and that, to the proprietors, the improvement of the land has been, in the final result, a miscalculation. He means, not that the land of Great Britain would not now sell for what has been laid out upon it, but that it would not sell for that amount plus the expense of making all the roads, canals, and railways. This is probably true, but is no more to the purpose, and no more important in political economy, than if the statement had been, that it would not sell for the sums laid out on it plus the national debt, or plus the cost of the French Revolutionary war, or any other expense incurred for a real or imaginary public advantage. The roads, railways, and canals were not constructed to give value to land: on the contrary, their natural effect was to lower its value, by rendering other and rival lands accessible: and the landlords of the southern counties actually petitioned Parliament against the turnpike roads on this very account.
The tendency of improved communications is to lower existing rents, by trenching on the monopoly of the land nearest to the places where large numbers of consumers are assembled. Roads and canals are not intended to raise the value of the land which already supplies the markets, but (among other purposes) to cheapen the supply, by letting in the produce of other and more distant lands; and the more effectually this purpose is attained, the lower rent will be. If we could imagine that the railways and canals of the United States, instead of only cheapening communication, did their business so effectually as to annihilate cost of carriage altogether, and enable the produce of Michigan to reach the market of New York as quickly and as cheaply as the produce of Long Island—the whole value of all the land of the United States (except such as lies convenient for building) would be annihilated; or rather, the best would only sell for the expense of clearing, and the government tax of a dollar and a quarter per acre; since land in Michigan, equal to the best in the United States, may be had in unlimited abundance by that amount of outlay. But it is strange that Mr. Carey should think this fact inconsistent with the Ricardo theory of rent. Admitting all that he asserts, it is still true that as long as there is land which yields no rent, the land which does yield rent, does so in consequence of some advantage which it enjoys, in fertility or vicinity to markets, over the other; and the measure of its advantage is also the measure of its rent. And the cause of its yielding rent is that it possesses a natural monopoly; the quantity of land, as favourably circumstanced as itself, not being sufficient to supply the market. These propositions constitute the theory of rent laid down by Ricardo; and if they are true, I cannot see that it signifies much whether the rent which the land yields at the present time, is greater or less than the interest of the capital which has been laid out to raise its value, together with the interest of the capital which has been laid out to lower its value.
Mr. Carey’s objection, however, has somewhat more of ingenuity than the arguments commonly met with against the theory of rent; a theorem which may be called the
pons asinorum of political economy, for there are, I am inclined to think, few persons who have refused their assent to it except from not having thoroughly understood it. The loose and inaccurate way in which it is often apprehended by those who affect to refute it, is very remarkable. Many, for instance, have imputed absurdity to Mr. Ricardo’s theory, because it is absurd to say that the
cultivation of inferior land is the cause of rent on the superior. Mr. Ricardo does not say that it is the cultivation of inferior land, but the
necessity of cultivating it, from the insufficiency of the superior land to feed a growing population: between which and the proposition imputed to him there is no less a difference than that between demand and supply. Others again allege as an objection against Ricardo, that if all land were of equal fertility, it might still yield a rent. But Ricardo says precisely the same. He says that if all lands were equally fertile, those which are nearer to their market than others, and are therefore less burthened with cost of carriage, would yield a rent equivalent to the advantage; and that the land yielding no rent would then be, not the least fertile, but the least advantageously situated, which the wants of the community required to be brought into cultivation. It is also distinctly a portion of Ricardo’s doctrine, that even apart from differences of situation, the land of a country supposed to be of uniform fertility would, all of it, on a certain supposition, pay rent: namely, if the demand of the community required that it should all be cultivated, and cultivated beyond the point at which a further application of capital begins to be attended with a smaller proportional return. It would be impossible to show that, except by forcible exaction, the whole land of a country can yield a rent on any other supposition.
§6. After this view of the nature and causes of rent, let us turn back to the subject of profits, and bring up for reconsideration one of the propositions laid down in the last chapter. We there stated, that the advances of the capitalist, or in other words, the expenses of production, consist solely in wages of labour; that whatever portion of the outlay is not wages, is previous profit, and whatever is not previous profit, is wages. Rent, however, being an element which it is impossible to resolve into either profits or wages, we were obliged, for the moment, to assume that the capitalist is not required to pay rent—to give an equivalent for the use of an appropriated natural agent: and I undertook to show in the proper place, that this is an allowable supposition, and that rent does not really form any part of the expenses of production, or of the advances of the capitalist. The grounds on which this assertion was made are now apparent. It is true that all tenant farmers, and many other classes of producers, pay rent. But we have now seen, that whoever cultivates land, paying a rent for it, gets in return for his rent an instrument of superior power to other instruments of the same kind for which no rent is paid. The superiority of the instrument is in exact proportion to the rent paid for it. If a few persons had steam-engines of superior power to all others in existence, but limited by physical laws to a number short of the demand, the rent which a manufacturer would be willing to pay for one of these steam-engines could not be looked upon as an addition to his outlay, because by the use of it he would save in his other expenses the equivalent of what it cost him: without it he could not do the same quantity of work, unless at an additional expense equal to the rent. The same thing is true of land. The real expenses of production are those incurred on the worst land, or by the capital employed in the least favourable circumstances. This land or capital pays, as we have seen, no rent; but the expenses to which it is subject, cause all other land or agricultural capital to be subjected to an equivalent expense in the form of rent. Whoever does pay rent gets back its full value in extra advantages, and the rent which he pays does not place him in a worse position than, but only in the same position as, his fellow-producer who pays no rent, but whose instrument is one of inferior efficiency.
We have now completed the exposition of the laws which regulate the distribution of the produce of land, labour, and capital, as far as it is possible to discuss those laws independently of the instrumentality by which in a civilized society the distribution is effected; the machinery of Exchange and Price. The more complete elucidation and final confirmation of the laws which we have laid down, and the deduction of their most important consequences, must be preceded by an explanation of the nature and working of that machinery—a subject so extensive and complicated as to require a separate Book.
Book II. Chapter XVI. Section 4
Book II. Chapter XVI. Section 5
Book II. Chapter XVI. Section 6