used in its most extensive signification, as applicable to every voluntary exertion.

According to the definition now given of the word action, the primary sources of our activity are the circumstances in which the acts of the will originate. Of these there are some which make a part of our constitution, and which, on that account, are called active principles. Such are hunger, thirst, the appetite which unites the sexes, curiosity, ambition, pity, resentment.

These active principles are also called powers of the will, because, by stimulating us in various ways to action, they afford exercise to our sense of duty and our other rational principles of action, and give occasion to our voluntary determinations as free agents.

III. Difficulty of the Study.] The study of this part of our constitution, although it may at first view seem to lie more open to our examination than the powers of the understanding, is attended with some difficulties peculiar to itself. For this various reasons may be assigned; among which there are two that seem principally to claim our attention.

1. When we wish to examine the nature of any of our intellectual principles, we can at all times subject the faculty in question to the scrutiny of reflection; and can institute whatever experiments with respect to it may be necessary for ascertaining its general laws. It is characteristic of all our operations purely intellectual to leave the mind cool and undisturbed, so that the exercise of the faculties concerned in them does not prevent us from an analytical investigation of their theory. The case is very different with our active powers, particularly with those which, from their violence and impetuosity, have the greatest influence on human happiness. When we are under the dominion of the power, or, in plainer language, when we are hurried by passion to the pursuit of a particular end, we feel no inclination to speculate concerning the mental phenomena. When the tumult subsides, and our curiosity is awakened concerning the past, the moment for observation and experiment is lost, and we are obliged to search for our facts in an imperfect recollection of what

was viewed, even in the first instance, through the most troubled and deceitful of all media.

Something connected with this is the following remark of Mr. Hume :-"Moral philosophy has this peculiar disadvantage, which is not to be found in natural, that, in collecting its experiments, it cannot make them purposely, with premeditation, and after such a manner as to satisfy itself concerning every particular difficulty that may arise. When I am at a loss to know the effects of one body upon another in any situation, I need only put them in that situation, and observe what results from it. But should I endeavour to clear up, after the same manner, any doubts in moral philosophy, by placing myself in the same case with that which I consider, it is evident that this reflection and premeditation would so disturb the operation of my natural principles, as must render it impossible to form any just conclusion from the phenomenon. We must therefore glean up our experiments in this science from a cautious observation of human life, and take them as they appear in the common course of the world, by men's behaviour in company, in affairs, and in their pleasures."*

2. Another circumstance which adds much to the difficulty of this branch of study is the great variety of our active principles, and the endless diversity of their combinations in the characters of men. The same action may proceed from very different, and even opposite, motives in the case of two individuals, and even in the same individual on different occasions; or an action which in one man proceeds from a single motive may, in another, proceed from a number of motives conspiring together and modifying each other's effects. The philosophers who have speculated on this subject have in general been misled by an excessive love of simplicity, and have attempted to explain the phenomena from the smallest possible number of data. Overlooking the real complication of our active principles, they have sometimes fixed on a single one, (good or bad, according as they were disposed to think well or ill of human nature,) and have deduced from it a plausible explanation of all the varieties of human character and conduct.

* Treatise of Human Nature, Vol. I., Introduction.

Our inquiries on this subject must be conducted in one of two ways, either by studying the characters of other men, or by studying our own. In the former way, we may undoubtedly collect many useful hints, and many facts to confirm or to limit our conclusions; but the conjectures we form concerning the motives of others are liable to so much uncertainty, that it is chiefly by attending to what passes in our own minds that we can reasonably hope to ascertain the general laws of our constitution as active and moral beings.

Even this plan of study, however, as I have already hinted, requires uncommon perseverance, and still more uncommon candor. The difficulty is great of attending to any of the operations of the mind; but this difficulty is much increased in those cases in which we are led by vanity or timidity to fancy that we have an interest in concealing the truth from our own knowledge.

Most men, perhaps, are disposed, in consequence of these and some other causes, to believe themselves better than they really are; and a few, there is reason to suspect, go into the opposite extreme, from the influence of false systems of philosophy or religion, or from the gloomy views inspired by a morbid melancholy.

When to these considerations we add the endless metaphysical disputes on the subject of the will, and of man's free agency, it may easily be conceived that the field of inquiry upon which we are now to enter abounds with questions not less curious and intricate than any of those which have been hitherto under our review. In point of practical importance some of them will be found in a still higher degree entitled to our attention.

IV. Division of the Active Principles.] In the further prosecution of this subject, I shall avoid, as much as possible, all technical divisions and classifications, and shall content myself with the following enumeration of our Active Principles, which I hope will be found sufficiently distinct and comprehensive for our purposes.

1. APPETITES.

2. DESIRES.

3. AFFECTIONS.

4. SELF-LOVE.

5. THE MORAL FACULTY.

The first three may be distinguished (for a reason which will afterwards appear) by the title of INSTINCTIVE OR IMPLANTED PROPENSITIES; the last two by the title of RATIONAL AND GOVERNING PRINCIPLES OF ACTION.*

* In the above enumeration I have departed widely from Dr. Reid's language. See his Essays on the Active Powers, Essay III., Parts I., II., and III. This great philosopher, with whom I am always unwilling to differ, refers our active principles to three classes, the mechanical, the animal, and the rational; using all these three words with what I think a very exceptionable latitude. On this occasion I shall only observe, that the word mechanical (under which he comprehends our instincts and habits) cannot, in my opinion, be properly applied to any of our active principles. It is indeed used, in this instance, merely as a term of distinction; but it seems to imply some theory concerning the nature of the principles comprehended under it, and is apt to suggest incorrect notions on the subject.

If I had been disposed to examine this part of our constitution with all the minute accuracy of which it is susceptible, I should have preferred the following arrangement to that which I have adopted, as well as to that proposed by Dr. Reid: - - 1. Of our original principles of action. 2. Of our acquired principles of action.

The original principles of action may be subdivided into the animal and the rational; to the former of which classes our instincts ought undoubtedly to be referred, as well as our appetites. In Dr. Reid's arrangement, nothing appears more unaccountable, if not capricious, than to call our appetites animal principles, because they are common to man and to the brutes; and, at the same time, to distinguish our instincts by the title of mechanical; when, of all our active propensities, there are none in which the nature of man bears so strong an analogy to that of the lower animals as in these instinctive impulses. Indeed, it is from the condition of the brutes that the word instinct is transferred to that of man by a sort of figure or metaphor.

Our acquired principles of action comprehend all those propensities to act which we acquire from habit. Such are our artificial appetites and artificial desires, and the various factitious motives of human conduct generated by association and fashion.

At present, it being useless for any of the purposes which I have in view to attempt so comprehensive and detailed an examination of the subject, I shall confine myself to the general enumeration already mentioned. As our appetites, our desires, and our affections, whether original or acquired, stand in the same common relation to the Moral Faculty (the illustration of which is the chief object of this volume), I purposely avoid those slighter and less important subdivisions which might be thought to savour unnecessarily of scholastic subtilty.

[For later classifications of our Active Principles, see Upham's Elements of Mental Philosophy, Vol. II., Introduction, Chap. ii., and Whewell's Elements of Morality, B. I. Chap. ii.]

BOOK I.

OF OUR INSTINCTIVE PRINCIPLES OF ACTION.

CHAPTER I.

OF OUR APPETITES.

1. Their Nature, Use, and Abuse.] This class of our Active Principles is distinguished by the following cir

1. They take their rise from the body, and are common to us with the brutes.

2. They are not constant, but occasional.

3. They are accompanied with an uneasy sensation, which is strong or weak in proportion to the strength or weakness of the appetite.

Our appetites are three in number, hunger, thirst, and the appetite of sex. Of these, two were intended for the preservation of the individual; the third for the continuation of the species; and without them reason would have been insufficient for these important purposes. Suppose, for example, that the appetite of hunger had been no part of our constitution, reason and experience might have satisfied us of the necessity of food to our preservation; but how should we have been able, without an implanted principle, to ascertain, according to the varying state of our animal economy, the proper seasons for eating, or the quantity of food that is salutary to the body? The lower animals not only receive this information from nature, but are, moreover, directed by instinct to the particular sort of food that is proper for them to use in health and in sickness. The senses of taste and smell, in the savage state of our species, are subservient, at least in some degree, to the same purpose.