Powers, though not a species of rights (for the two sorts of fictitious entities, termed a power and a right, are altogether disparate) are yet so far included under rights, that wherever the word power maybe employed, the word right may also be employed: The reason is, that wherever you may speak of a person as having a power, you may also speak of him as having a right to such power: but the converse of this proposition does not hold good: there are cases in which, though you may speak of a man as having a right, you cannot speak of him as having a power or in any other way make any mention of that word. On various occasions you have a right for instance, to the services of the magistrate: but if you are a private person, you have no power over him: all the power is on his side. This being the case, as the word right was employed, the word power might perhaps, without any deficiency in the sense, have been omitted. On the present occasion however, as in speaking of trusts this word is commonly made more use of than the word right, it seemed most eligible, for the sake of perspicuity, to insert them both.

It may be expected that, since the word trust has been here expounded, the words power and right, upon the meaning of which the exposition of the word trust is made to depend, should be expounded also: and certain it is, that no two words can stand more in need of it than these do. Such exposition I accordingly set about to give, and indeed have actually drawn up: but the details into which I found it necessary to enter for this purpose, were of such length as to take up more room than could consistently be allotted to them in this place. With respect to these words, therefore, and a number of others, such as possession, title, and the like, which in point of import are inseparably connected with them, instead of exhibiting the exposition itself, I must content myself with giving a general idea of the plan which I have pursued in framing it: and as to every thing else, I must leave the import of them to rest upon whatever footing it may happen to stand upon in the apprehension of each reader. Power and right, and the whole tribe of fictitious entities of this stamp, are all of them, in the sense which belongs to them in a book of jurisprudence, the results of some manifestation or other of the legislator's will with respect to such or such an act. Now every such manifestation is either a prohibition, a command, or their respective negations; viz. a permission, and the declaration which the legislator makes of his will when on any occasion he leaves an act uncommanded. Now, to render the expression of the rule more concise, the commanding of a positive act may be represented by the prohibition of the negative act which is opposed to it. To know then how to expound a right, carry your eye to the act which in the circumstances in question would be a violation of that right: the law creates the right by prohibiting that act. Power, whether over a man's own person, or over other persons or over things, is constituted in the first instance by permission: but in as far as the law takes an active part in corroborating it, it is created by prohibition, and by command: by prohibition of such acts (on the part of other persons) as are judged incompatible with the exercise of it; and upon occasion, by command of such acts as are judged to be necessary for the removal of such or such obstacles of the number of those which may occur to impede the exercise of it. For every right which the law confers on one party, whether that party be an individual, a subordinate glass of individuals, or the public, it thereby imposes on some other party a duty or obligation. But there may be laws which command or prohibit acts, that is, impose duties, without any other view than the benefit of the agent: these generate no rights: duties, therefore, may be either extra-regarding or self-regarding: extra-regarding have rights to correspond to them: self-regarding, none.

That the exposition of the words power and right must, in order to be correct, enter into a great variety of details, may be presently made appear. One branch of the system of rights and powers, and but one, are those of which property is composed: to be correct, then, it must, among other things, be applicable to the whole tribe of modifications of which property, is susceptible. But the commands and prohibitions, by which the powers and rights that compose those several modifications are vented, are so many different forms: to comprise the exposition in question within the compass of a single paragraph, would therefore be impossible: to take as many paragraphs for it as would be necessary, in order to exhibit these' different forms, would be to engage in a detail so ample, that the analyst of the several possible species of property would compose only a part of it. This labour, uninviting as it was, I have accordingly undergone: but the result of it, as may well be imagined, seemed too voluminous and minute to be exhibited in an outline like the present. Happily it is not necessary except only for the scientific purpose of arrangement, to the understanding of any thing that need be said on the penal branch of the art of legislation. In a work which should treat of the civil branch of that art, it would find its proper place: and in such a work, if conducted upon the plan of the present one, it would be indispensable. Of the limits which seem to separate the one of these branches from the other, a pretty ample description will be found in the next chapter: from which some further lights respecting the course to be taken for developing the notions to be annexed to the words right and power, may incidentally be collected. See in particular §3 and 4. See also par. lv. of the present chapter.

I might have cut this matter very short, by proceeding in the usual strain, and saying, that a power was a faculty, and that a right was a privilege, and so on, following the beaten track of definition. But the inanity of such a method, in cases like the present, has been already pointed out (see Fragment of Government, ch. v. § 6, note.): a power is not a---any thing: neither is a right a---any thing: the case is they have neither of them any superior genus: these, together with duty, obligation, and a multitude of others of the same stamp, being of the number of those fictitious entities, of which the import can by no other mean be illustrated than by showing the relation which they bear to real ones.

IPML Chapter 16 Section 2 Part 4