We proceed to verify these a.s.sertions by an examination of the most generally received definitions of the science.
1. First, as to the vulgar notion of the nature and object of Political Economy, we shall not be wide of the mark if we state it to be something to this effect:--That Political Economy is a science which teaches, or professes to teach, in what manner a nation may be made rich. This notion of what const.i.tutes the science, is in some degree countenanced by the t.i.tle and arrangement which Adam Smith gave to his invaluable work. A systematic treatise on Political Economy, he chose to call an _Inquiry into the Nature and Causes of the Wealth of Nations_; and the topics are introduced in an order suitable to that view of the purpose of his book.
With respect to the definition in question, if definition it can be called which is not found in any set form of words, but left to be arrived at by a process of abstraction from a hundred current modes of speaking on the subject; it seems liable to the conclusive objection, that it confounds the essentially distinct, though closely connected, ideas of _science_ and _art_. These two ideas differ from one another as the understanding differs from the will, or as the indicative mood in grammar differs from the imperative. The one deals in facts, the other in precepts. Science is a collection of _truths_; art, a body of _rules_, or directions for conduct. The language of science is, This is, or, This is not; This does, or does not, happen. The language of art is, Do this; Avoid that. Science takes cognizance of a _phenomenon_, and endeavours to discover its _law_; art proposes to itself an _end_, and looks out for _means_ to effect it.
If, therefore, Political Economy be a science, it cannot be a collection of practical rules; though, unless it be altogether a useless science, practical rules must be capable of being founded upon it. The science of mechanics, a branch of natural philosophy, lays down the laws of motion, and the properties of what are called the mechanical powers. The art of practical mechanics teaches how we may avail ourselves of those laws and properties, to increase our command over external nature. An art would not be an art, unless it were founded upon a scientific knowledge of the properties of the subject-matter: without this, it would not be philosophy, but empiricism; [Greek: empeiria,] not [Greek: technae,] in Plato"s sense. Rules, therefore, for making a nation increase in wealth, are not a science, but they are the results of science. Political Economy does not of itself instruct how to make a nation rich; but whoever would be qualified to judge of the means of making a nation rich, must first be a political economist.
2. The definition most generally received among instructed persons, and laid down in the commencement of most of the professed treatises on the subject, is to the following effect:--That Political Economy informs us of the laws which regulate the production, distribution, and consumption of wealth. To this definition is frequently appended a familiar ill.u.s.tration. Political Economy, it is said, is to the state, what domestic economy is to the family.
This definition is free from the fault which we pointed out in the former one. It distinctly takes notice that Political Economy is a science and not an art; that it is conversant with laws of nature, not with maxims of conduct, and teaches us how things take place of themselves, not in what manner it is advisable for us to shape them, in order to attain some particular end.
But though the definition is, with regard to this particular point, un.o.bjectionable, so much can scarcely be said for the accompanying ill.u.s.tration; which rather sends back the mind to the current loose notion of Political Economy already disposed of. Political Economy is really, and is stated in the definition to be, a science: but domestic economy, so far as it is capable of being reduced to principles, is an art. It consists of rules, or maxims of prudence, for keeping the family regularly supplied with what its wants require, and securing, with any given amount of means, the greatest possible quant.i.ty of physical comfort and enjoyment. Undoubtedly the beneficial _result_, the great practical _application_ of Political Economy, would be to accomplish for a nation something like what the most perfect domestic economy accomplishes for a single household: but supposing this purpose realised, there would be the same difference between the rules by which it might be effected, and Political Economy, which there is between the art of gunnery and the theory of projectiles, or between the rules of mathematical land-surveying and the science of trigonometry.
The definition, though not liable to the same objection as the ill.u.s.tration which is annexed to it, is itself far from unexceptionable.
To neither of them, considered as standing at the head of a treatise, have we much to object. At a very early stage in the study of the science, anything more accurate would be useless, and therefore pedantic. In a merely initiatory definition, scientific precision is not required: the object is, to insinuate into the learner"s mind, it is scarcely material by what means, some general preconception of what are the uses of the pursuit, and what the series of topics through which he is about to travel. As a mere antic.i.p.ation or _ebauche_ of a definition, intended to indicate to a learner as much as he is able to understand before he begins, of the nature of what is about to be taught to him, we do not quarrel with the received formula. But if it claims to be admitted as that complete _definitio_ or boundary-line, which results from a thorough exploring of the whole extent of the subject, and is intended to mark the exact place of Political Economy among the sciences, its pretension cannot be allowed.
"The science of the laws which regulate the production, distribution, and consumption of wealth." The term wealth is surrounded by a haze of floating and vapoury a.s.sociations, which will let nothing that is seen through them be shewn distinctly. Let us supply its place by a periphrasis. Wealth is defined, all objects useful or agreeable to mankind, except such as can be obtained in indefinite quant.i.ty without labour. Instead of all objects, some authorities say, all material objects: the distinction is of no moment for the present purpose.
To confine ourselves to production: If the laws of the production of all objects, or even of all material objects, which are useful or agreeable to mankind, were comprised in Political Economy, it would be difficult to say where the science would end: at the least, all or nearly all physical knowledge would be included in it. Corn and cattle are material objects, in a high degree useful to mankind. The laws of the production of the one include the principles of agriculture; the production of the other is the subject of the art of cattle-breeding, which, in so far as really an art, must be built upon the science of physiology. The laws of the production of manufactured articles involve the whole of chemistry and the whole of mechanics. The laws of the production of the wealth which is extracted from the bowels of the earth, cannot be set forth without taking in a large part of geology.
When a definition so manifestly surpa.s.ses in extent what it professes to define, we must suppose that it is not meant to be interpreted literally, though the limitations with which it is to be understood are not stated.
Perhaps it will be said, that Political Economy is conversant with such only of the laws of the production of wealth as are applicable to _all_ kinds of wealth: those which relate to the details of particular trades or employments forming the subject of other and totally distinct sciences.
If, however, there were no more in the distinction between Political Economy and physical science than this, the distinction, we may venture to affirm, would never have been made. No similar division exists in any other department of knowledge. We do not break up zoology or mineralogy into two parts; one treating of the properties common to all animals, or to all minerals; another conversant with the properties peculiar to each particular species of animals or minerals. The reason is obvious; there is no distinction _in kind_ between the general laws of animal or of mineral nature and the peculiar properties of particular species. There is as close an a.n.a.logy between the general laws and the particular ones, as there is between one of the general laws and another: most commonly, indeed, the particular laws are but the complex result of a plurality of general laws modifying each other. A separation, therefore, between the general laws and the particular ones, merely because the former are general and the latter particular, would run counter both to the strongest motives of convenience and to the natural tendencies of the mind. If the case is different with the laws of the production of wealth, it must be because, in this case, the general laws differ in kind from the particular ones. But if so, the difference in kind is the radical distinction, and we should find out what that is, and found our definition upon it.
But, further, the recognised boundaries which separate the field of Political Economy from that of physical science, by no means correspond with the distinction between the truths which concern all kinds of wealth and those which relate only to some kinds. The three laws of motion, and the law of gravitation, are common, as far as human observation has yet extended, to all matter; and these, therefore, as being among the laws of the production of all wealth, should form part of Political Economy. There are hardly any of the processes of industry which do not partly depend upon the properties of the lever; but it would be a strange cla.s.sification which included those properties among the truths of Political Economy. Again, the latter science has many inquiries altogether as special, and relating as exclusively to particular sorts of material objects, as any of the branches of physical science. The investigation of some of the circ.u.mstances which regulate the price of corn, has as little to do with the laws common to the production of all wealth, as any part of the knowledge of the agriculturist. The inquiry into the rent of mines or fisheries, or into the value of the precious metals, elicits truths which have immediate reference to the production solely of a peculiar kind of wealth; yet these are admitted to be correctly placed in the science of Political Economy.
The real distinction between Political Economy and physical science must be sought in something deeper than the nature of the subject-matter; which, indeed, is for the most part common to both. Political Economy, and the scientific grounds of all the useful arts, have in truth one and the same subject-matter; namely, the objects which conduce to man"s convenience and enjoyment: but they are, nevertheless, perfectly distinct branches of knowledge.
3. If we contemplate the whole field of human knowledge, attained or attainable, we find that it separates itself obviously, and as it were spontaneously, into two divisions, which stand so strikingly in opposition and contradistinction to one another, that in all cla.s.sifications of our knowledge they have been kept apart. These are, _physical_ science, and _moral_ or psychological science. The difference between these two departments of our knowledge does not reside in the subject-matter with which they are conversant: for although, of the simplest and most elementary parts of each, it may be said, with an approach to truth, that they are concerned with different subject- matters--namely, the one with the human mind, the other with all things whatever except the mind; this distinction does not hold between the higher regions of the two. Take the science of politics, for instance, or that of law: who will say that these are physical sciences? and yet is it not obvious that they are conversant fully as much with matter as with mind? Take, again, the theory of music, of painting, of any other of the fine arts, and who will venture to p.r.o.nounce that the facts they are conversant with belong either wholly to the cla.s.s of matter, or wholly to that of mind?
The following seems to be the _rationale_ of the distinction between physical and moral science.
In all the intercourse of man with nature, whether we consider him as acting upon it, or as receiving impressions from it, the effect or phenomenon depends upon causes of two kinds: the properties of the object acting, and those of the object acted upon. Everything which can possibly happen in which man and external things, are jointly concerned, results from the joint operation of a law or laws of matter, and a law or laws of the human mind. Thus the production of corn by human labour is the result of a law of mind, and many laws of matter. The laws of matter are those properties of the soil and of vegetable life which cause the seed to germinate in the ground, and those properties of the human body which render food necessary to its support. The law of mind is, that man desires to possess subsistence, and consequently wills the necessary means of procuring it.
Laws of mind and laws of matter are so dissimilar in their nature, that it would be contrary to all principles of rational arrangement to mix them up as part of the same study. In all scientific methods, therefore, they are placed apart. Any compound effect or phenomenon which depends both on the properties of matter and on those of mind, may thus become the subject of two completely distinct sciences, or branches of science; one, treating of the phenomenon in so far as it depends upon the laws of matter only; the other treating of it in so far as it depends upon the laws of mind.
The physical sciences are those which treat of the laws of matter, and of all complex phenomena in so far as dependent upon the laws of matter.
The mental or moral sciences are those which treat of the laws of mind, and of all complex phenomena in so far as dependent upon the laws of mind.
Most of the moral sciences presuppose physical science; but few of the physical sciences presuppose moral science. The reason is obvious. There are many phenomena (an earthquake, for example, or the motions of the planets) which depend upon the laws of matter exclusively; and have nothing whatever to do with the laws of mind. Many, therefore, of the physical sciences may be treated of without any reference to mind, and as if the mind existed as a recipient of knowledge only, not as a cause producing effects. But there are no phenomena which depend exclusively upon the laws of mind; even the phenomena of the mind itself being partially dependent upon the physiological laws of the body. All the mental sciences, therefore, not excepting the pure science of mind, must take account of a great variety of physical truths; and (as physical science is commonly and very properly studied first) may be said to presuppose them, taking up the complex phenomena where physical science leaves them.
Now this, it will be found, is a precise statement of the relation in which Political Economy stands to the various sciences which are tributary to the arts of production.
The laws of the production of the objects which const.i.tute wealth, are the subject-matter both of Political Economy and of almost all the physical sciences. Such, however, of those laws as are purely laws of matter, belong to physical science, and to that exclusively. Such of them as are laws of the human mind, and no others, belong to Political Economy, which finally sums up the result of both combined.
Political Economy, therefore, presupposes all the physical sciences; it takes for granted all such of the truths of those sciences as are concerned in the production of the objects demanded by the wants of mankind; or at least it takes for granted that the physical part of the process takes place somehow. It then inquires what are the phenomena of _mind_ which are concerned in the production and distribution [8] of those same objects; it borrows from the pure science of mind the laws of those phenomena, and inquires what effects follow from these mental laws, acting in concurrence with those physical one. [9]
From the above considerations the following seems to come out as the correct and complete definition of Political Economy:--"The science which treats of the production and distribution of wealth, so far as they depend upon the laws of human nature." Or thus--science relating to the moral or psychological laws of the production and distribution of wealth."
For popular use this definition is amply sufficient, but it still falls short of the complete accuracy required for the purposes of the philosopher. Political Economy does not treat of the production and distribution of wealth in all states of mankind, but only in what is termed the social state; nor so far as they depend upon the laws of human nature, but only so far as they depend upon a certain portion of those laws. This, at least, is the view which must be taken of Political Economy, if we mean it to find any place in an encyclopedical division of the field of science. On any other view, it either is not science at all, or it is several sciences. This will appear clearly, if, on the one hand, we take a general survey of the moral sciences, with a view to a.s.sign the exact place of Political Economy among them; while, on the other, we consider attentively the nature of the methods or processes by which the truths which are the object of those sciences are arrived at.
Man, who, considered as a being having a moral or mental nature, is the subject-matter of all the moral sciences, may, with reference to that part of his nature, form the subject of philosophical inquiry under several distinct hypotheses. We may inquire what belongs to man considered individually, and as if no human being existed besides himself; we may next consider him as coming into contact with other individuals; and finally, as living in a state of _society_, that is, forming part of a body or aggregation of human beings, systematically co-operating for common purposes. Of this last state, political government, or subjection to a common superior, is an ordinary ingredient, but forms no necessary part of the conception, and, with respect to our present purpose, needs not be further adverted to.
Those laws or properties of human nature which appertain to man as a mere individual, and do not presuppose, as a necessary condition, the existence of other individuals (except, perhaps, as mere instruments or means), form a part of the subject of pure mental philosophy. They comprise all the laws of the mere intellect, and those of the purely self-regarding desires.
Those laws of human nature which relate to the feelings called forth in a human being by other individual human or intelligent beings, as such; namely, the _affections_, the _conscience_, or feeling of duty, and the love of _approbation_; and to the conduct of man, so far as it depends upon, or has relation to, these parts of his nature--form the subject of another portion of pure mental philosophy, namely, that portion of it on which _morals_, or _ethics_, are founded. For morality itself is not a science, but an art; not truths, but rules. The truths on which the rules are founded are drawn (as is the case in all arts) from a variety of sciences; but the princ.i.p.al of them, and those which are most nearly peculiar to this particular art, belong to a branch of the science of mind.
Finally, there are certain principles of human nature which are peculiarly connected with the ideas and feelings generated in man by living in a state of _society_, that is, by forming part of a union or aggregation of human beings for a common purpose or purposes. Few, indeed, of the elementary laws of the human mind are peculiar to this state, almost all being called into action in the two other states. But those simple laws of human nature, operating in that wider field, give rise to results of a sufficiently universal character, and even (when compared with the still more complex phenomena of which they are the determining causes) sufficiently simple, to admit of being called, though in a somewhat looser sense, _laws_ of society, or laws of human nature in the social state. These laws, or general truths, form the subject of a branch of science which may be aptly designated from the t.i.tle of _social economy_; somewhat less happily by that of _speculative politics_, or the _science_ of politics, as contradistinguished from the art. This science stands in the same relation to the social, as anatomy and physiology to the physical body. It shows by what principles of his nature man is induced to enter into a state of society; how this feature in his position acts upon his interests and feelings, and through them upon his conduct; how the a.s.sociation tends progressively to become closer, and the co-operation extends itself to more and more purposes; what those purposes are, and what the varieties of means most generally adopted for furthering them; what are the various relations which establish themselves among human beings as the ordinary consequence of the social union; what those which are different in different states of society; in what historical order those states tend to succeed one another; and what are the effects of each upon the conduct and character of man.
This branch of science, whether we prefer to call it social economy, speculative politics, or the natural history of society, presupposes the whole science of the nature of the individual mind; since all the laws of which the latter science takes cognizance are brought into play in a state of society, and the truths of the social science are but statements of the manner in which those simple laws take effect in complicated circ.u.mstances. Pure mental philosophy, therefore, is an essential part, or preliminary, of political philosophy. The science of social economy embraces every part of man"s nature, in so far as influencing the conduct or condition of man in society; and therefore may it be termed speculative politics, as being the scientific foundation of practical politics, or the art of government, of which the art of legislation is a part. [10]
It is to _this_ important division of the field of science that one of the writers who have most correctly conceived and copiously ill.u.s.trated its nature and limits,--we mean M. Say,--has chosen to give the name Political Economy. And, indeed, this large extension of the signification of that term is countenanced by its etymology. But the words "political economy" have long ceased to have so large a meaning.
Every writer is ent.i.tled to use the words which are his tools in the manner which he judges most conducive to the general purposes of the exposition of truth; but he exercises this discretion under liability to criticism: and M. Say seems to have done in this instance, what should never be done without strong reasons; to have altered the meaning of a name which was appropriated to a particular purpose (and for which, therefore, a subst.i.tute must be provided), in order to transfer it to an object for which it was easy to find a more characteristic denomination.
What is now commonly understood by the term "Political Economy" is not the science of speculative politics, but a branch of that science. It does not treat of the whole of man"s nature as modified by the social state, nor of the whole conduct of man in society. It is concerned with him solely as a being who desires to possess wealth, and who is capable of judging of the comparative efficacy of means for obtaining that end.
It predicts only such of the phenomena of the social state as take place in consequence of the pursuit of wealth. It makes entire abstraction of every other human pa.s.sion or motive; except those which may be regarded as perpetually antagonizing principles to the desire of wealth, namely, aversion to labour, and desire of the present enjoyment of costly indulgences. These it takes, to a certain extent, into its calculations, because these do not merely, like other desires, occasionally conflict with the pursuit of wealth, but accompany it always as a drag, or impediment, and are therefore inseparably mixed up in the consideration of it. Political Economy considers mankind as occupied solely in acquiring and consuming wealth; and aims at showing what is the course of action into which mankind, living in a state of society, would be impelled, if that motive, except in the degree in which it is checked by the two perpetual counter-motives above adverted to, were absolute ruler of all their actions. Under the influence of this desire, it shows mankind acc.u.mulating wealth, and employing that wealth in the production of other wealth; sanctioning by mutual agreement the inst.i.tution of property; establishing laws to prevent individuals from encroaching upon the property of others by force or fraud; adopting various contrivances for increasing the productiveness of their labour; settling the division of the produce by agreement, under the influence of compet.i.tion (compet.i.tion itself being governed by certain laws, which laws are therefore the ultimate regulators of the division of the produce); and employing certain expedients (as money, credit, &c.) to facilitate the distribution. All these operations, though many of them are really the result of a plurality of motives, are considered by Political Economy as flowing solely from the desire of wealth. The science then proceeds to investigate the laws which govern these several operations, under the supposition that man is a being who is determined, by the necessity of his nature, to prefer a greater portion of wealth to a smaller in all cases, without any other exception than that const.i.tuted by the two counter-motives already specified. Not that any political economist was ever so absurd as to suppose that mankind are really thus const.i.tuted, but because this is the mode in which science must necessarily proceed.
When an effect depends upon a concurrence of causes, those causes must be studied one at a time, and their laws separately investigated, if we wish, through the causes, to obtain the power of either predicting or controlling the effect; since the law of the effect is compounded of the laws of all the causes which determine it. The law of the centripetal and that of the tangential force must have been known before the motions of the earth and planets could be explained, or many of them predicted.
The same is the case with the conduct of man in society. In order to judge how he will act under the variety of desires and aversions which are concurrently operating upon him, we must know how he would act under the exclusive influence of each one in particular. There is, perhaps, no action of a man"s life in which he is neither under the immediate nor under the remote influence of any impulse but the mere desire of wealth.
With respect to those parts of human conduct of which wealth is not even the princ.i.p.al object, to these Political Economy does not pretend that its conclusions are applicable. But there are also certain departments of human affairs, in which the acquisition of wealth is the main and acknowledged end. It is only of these that Political Economy takes notice. The manner in which it necessarily proceeds is that of treating the main and acknowledged end as if it were the sole end; which, of all hypotheses equally simple, is the nearest to the truth. The political economist inquires, what are the actions which would be produced by this desire, if, within the departments in question, it were unimpeded by any other. In this way a nearer approximation is obtained than would otherwise be practicable, to the real order of human affairs in those departments. This approximation is then to be corrected by making proper allowance for the effects of any impulses of a different description, which can be shown to interfere with the result in any particular case.
Only in a few of the most striking cases (such as the important one of the principle of population) are these corrections interpolated into the expositions of Political Economy itself; the strictness of purely scientific arrangement being thereby somewhat departed from, for the sake of practical utility. So far as it is known, or may be presumed, that the conduct of mankind in the pursuit of wealth is under the collateral influence of any other of the properties of our nature than the desire of obtaining the greatest quant.i.ty of wealth with the least labour and self-denial, the conclusions of Political Economy will so far fail of being applicable to the explanation or prediction of real events, until they are modified by a correct allowance for the degree of influence exercised by the other cause.
Political Economy, then, may be defined as follows; and the definition seems to be complete:--
"The science which traces the laws of such of the phenomena of society as arise from the combined operations of mankind for the production of wealth, in so far as those phenomena are not modified by the pursuit of any other object."
But while this is a correct definition of Political Economy as a portion of the field of science, the didactic writer on the subject will naturally combine in his exposition, with the truths of the pure science, as many of the practical modifications as will, in his estimation, be most conducive to the usefulness of his work.
The above attempt to frame a stricter definition of the science than what are commonly received as such, may be thought to be of little use; or, at best, to be chiefly useful in a general survey and cla.s.sification of the sciences, rather than as conducing to the more successful pursuit of the particular science in question. We think otherwise, and for this reason; that, with the consideration of the definition of a science, is inseparably connected that of the _philosophic method_ of the science; the nature of the process by which its investigations are to be carried on, its truths to be arrived at.
Now, in whatever science there are systematic differences of opinion --which is as much as to say, in all the moral or mental sciences, and in Political Economy among the rest; in whatever science there exist, among those who have attended to the subject, what are commonly called differences of principle, as distinguished from differences of matter-of-fact or detail,--the cause will be found to be, a difference in their conceptions of the philosophic method of the science. The parties who differ are guided, either knowingly or unconsciously, by different views concerning the nature of the evidence appropriate to the subject. They differ not solely in what they believe themselves to see, but in the quarter whence they obtained the light by which they think they see it.
The most universal of the forms in which this difference of method is accustomed to present itself, is the ancient feud between what is called theory, and what is called practice or experience. There are, on social and political questions, two kinds of reasoners: there is one portion who term themselves practical men, and call the others theorists; a t.i.tle which the latter do not reject, though they by no means recognise it as peculiar to them. The distinction between the two is a very broad one, though it is one of which the language employed is a most incorrect exponent. It has been again and again demonstrated, that those who are accused of despising facts and disregarding experience build and profess to build wholly upon facts and experience; while those who disavow theory cannot make one step without theorizing. But, although both cla.s.ses of inquirers do nothing but theorize, and both of them consult no other guide than experience, there is this difference between them, and a most important difference it is: that those who are called practical men require _specific_ experience, and argue wholly _upwards_ from particular facts to a general conclusion; while those who are called theorists aim at embracing a wider field of experience, and, having argued upwards from particular facts to a general principle including a much wider range than that of the question under discussion, then argue _downwards_ from that general principle to a variety of specific conclusions.
Suppose, for example, that the question were, whether absolute kings were likely to employ the powers of government for the welfare or for the oppression of their subjects. The practicals would endeavour to determine this question by a direct induction from the conduct of particular despotic monarchs, as testified by history. The theorists would refer the question to be decided by the test not solely of our experience of kings, but of our experience of men. They would contend that an observation of the tendencies which human nature has manifested in the variety of situations in which human beings have been placed, and especially observation of what pa.s.ses in our own minds, warrants us in inferring that a human being in the situation of a despotic king will make a bad use of power; and that this conclusion would lose nothing of its certainty even if absolute kings had never existed, or if history furnished us with no information of the manner in which they had conducted themselves.
The first of these methods is a method of induction, merely; the last a mixed method of induction and ratiocination. The first may be called the method _a posteriori;_ the latter, the method _a priori_. We are aware that this last expression is sometimes used to characterize a supposed mode of philosophizing, which does not profess to be founded upon experience at all. But we are not acquainted with any mode of philosophizing, on political subjects at least, to which such a description is fairly applicable. By the method _a posteriori_ we mean that which requires, as the basis of its conclusions, not experience merely, but specific experience. By the method _a priori_ we mean (what has commonly been meant) reasoning from an a.s.sumed hypothesis; which is not a practice confined to mathematics, but is of the essence of all science which admits of general reasoning at all. To verify the hypothesis itself _a posteriori_, that is, to examine whether the facts of any actual case are in accordance with it, is no part of the business of science at all, but of the _application_ of science.
In the definition which we have attempted to frame of the science of Political Economy, we have characterized it as essentially an _abstract_ science, and its method as the method _a priori_. Such is undoubtedly its character as it has been understood and taught by all its most distinguished teachers. It reasons, and, as we contend, must necessarily reason, from a.s.sumptions, not from facts. It is built upon hypotheses, strictly a.n.a.logous to those which, under the name of definitions, are the foundation of the other abstract sciences. Geometry presupposes an arbitrary definition of a line, "that which has length but not breadth."
Just in the same manner does Political Economy presuppose an arbitrary definition of man, as a being who invariably does that by which he may obtain the greatest amount of necessaries, conveniences, and luxuries, with the smallest quant.i.ty of labour and physical self-denial with which they can be obtained in the existing state of knowledge. It is true that this definition of man is not formally prefixed to any work on Political Economy, as the definition of a line is prefixed to Euclid"s Elements; and in proportion as by being so prefixed it would be less in danger of being forgotten, we may see ground for regret that this is not done. It is proper that what is a.s.sumed in every particular case, should once for all be brought before the mind in its full extent, by being somewhere formally stated as a general maxim. Now, no one who is conversant with systematic treatises on Political Economy will question, that whenever a political economist has shown that, by acting in a particular manner, a labourer may obviously obtain higher wages, a capitalist larger profits, or a landlord higher rent, he concludes, as a matter of course, that they will certainly act in that manner. Political Economy, therefore, reasons from _a.s.sumed_ premises--from premises which might be totally without foundation in fact, and which are not pretended to be universally in accordance with it. The conclusions of Political Economy, consequently, like those of geometry, are only true, as the common phrase is, _in the abstract_; that is, they are only true under certain suppositions, in which none but general causes--causes common to the _whole cla.s.s_ of cases under consideration--are taken into the account.
This ought not to be denied by the political economist. If he deny it, then, and then only, he places himself in the wrong. The _a priori_ method which is laid to his charge, as if his employment of it proved his whole science to be worthless, is, as we shall presently show, the only method by which truth can possibly be attained in any department of the social science. All that is requisite is, that he be on his guard not to ascribe to conclusions which are grounded upon an hypothesis a different kind of certainty from that which really belongs to them. They would be true without qualification, only in a case which is purely imaginary. In proportion as the actual facts recede from the hypothesis, he must allow a corresponding deviation from the strict letter of his conclusion; otherwise it will be true only of things such as he has arbitrarily supposed, not of such things as really exist. That which is true in the abstract, is always true in the concrete with proper _allowances_. When a certain cause really exists, and if left to itself would infallibly produce a certain effect, that same effect, _modified_ by all the other concurrent causes, will correctly correspond to the result really produced.
The conclusions of geometry are not strictly true of such lines, angles, and figures, as human hands can construct. But no one, therefore, contends that the conclusions of geometry are of no utility, or that it would be better to shut up Euclid"s Elements, and content ourselves with "practice" and "experience."