that he has written on this subject, I find this word impression sometimes used to signify an operation of the mind, sometimes the object of the operation; but, for the most part, it is a vague and indetermined word that signifies both.

I know not whether it may be considered as an apology for such abuse of words, in an author who understood the language so well, and used it with so great propriety in writing on other subjects, [30] that Mr Hume's system, with regard to the mind, required a language of a different structure from the common: or, if expressed in plain English, would have been too shocking to the common sense of mankind. To give an instance or two of this. If a man receives a present on which he puts a high value, if he see and handle it, and put it in his pocket, this, says Mr Hume, is an impression. If the man only dream that he received such a present, this is an idea. Wherein lies the difference between this impression and this idea-between the dream and the reality? They are different classes or species, says Mr Hume so far all men will agree with him. But he adds, that they are distinguished only by different degrees of force and vivacity. Here he insinuates a tenet of his own, in contradiction to the commonsense of mankind. Common sense convinces every man, that a lively dream is no nearer to a reality than a faint one; and that, if a man should dream that he had all the wealth of Croesus, it would not put one farthing in his pocket. It is impossible to fabricate arguments against such undeniable principles, without confounding the meaning of words. In like manner, if a man would persuade me that the moon which I see, and my seeing it, are not two things, but one and the same thing, he will answer his purpose less by arguing this point in plain English, than by confounding the two under one namesuch as that of an impression. For such is the power of words, that, if we can be brought to the habit of calling two things that are connected by the same: пате, we are the more easily led to believe them to be one and the same thing.

Let us next consider the proper meaning of the word impression in English, that we may see how far it is fit to express either the operations of the mind or their objects. When a figure is stamped upon a body by pressure, that figure is called an impression, as the impression of a seal on wax, of [31] printing-types, or of a copperplate on paper. This seems now to be the literal sense of the word; the effect borrowing its name from the cause. But, by metaphor or analogy, like most other words, its meaning is extended, so as to signify any change pro

See below, under p. 338.-H.

duced in a body by the operation of some external cause. A blow of the hand makes no impression on a stone wall; but a battery of cannon may. The moon raises a tide in the ocean, but makes no impression on rivers and lakes.

When we speak of making an impression on the mind, the word is carried still farther from its literal meaning; use, however, which is the arbiter of language, authorizes this application of it-as when we say that admonition and reproof make little impression on those who are confirmed in bad habits. The same discourse delivered in one way makes a strong impression on the hearers; delivered in another way, it makes no impression at all.

It may be observed that, in such examples, an impression made on the mind always implies some change of purpose or will; some new habit produced, or some former habit weakened; some passion raised or allayed. When such changes are produced by persuasion, example, or any external cause, we say that such causes make an impression upon the mind; but, when things are seen, or heard, or apprehended, without producing any passion or emotion, we say that they make no impression.

In the most extensive sense, an impression is a change produced in some passive subject by the operation of an external cause. If we suppose an active being to produce any change in itself by its own active power, this is never called an impression. It is the act or operation of the being itself, not an impression upon it. From this it appears, that to give the name of an impression to any effect produced in the mind, is to suppose that the mind does not act at all in the production of that effect. If seeing, hearing, desiring, willing, be operations of the mind, they cannot be impressions. If [32] they be impressions, they cannot be operations of the mind. In the structure of all languages, they are considered as acts or operations of the mind itself, and the names given them imply this. To call them impressions, therefore, is to trespass against the structure, not of a particular language only, but of all languages.

If the word impression be an improper word to signify the operations of the mind, it is at least as improper to signify their objects; for would any man be thought to speak with propriety, who should say that the sun is an impression, that the earth and the sea are impressions?

It is commonly believed, and taken for granted, that every language, if it be sufficiently copious in words, is equally fit to express all opinions, whether they be true

just now explained; and, in this sense, it has no object; the feeling and the thing felt are one and the same. [35]

Perhaps betwixt feeling, taken in this last sense, and sensation, there may be this small difference, that sensation is most commonly used to signify those feelings which we have by our external senses and bodily appetites, and all our bodily pains and pleasures. But there are feelings of a nobler nature accompanying our affections, our moral judgments, and our determinations in matters of taste, to which the word sensation is less properly applied.

I have premised these observations on the meaning of certain words that frequently occur in treating of this subject, for two reasons: First, That I may be the better understood when I use them; and, Secondly, That those who would make any progress in this branch of science, may accustom themselves to attend very carefully to the meaning of words that are used in it. They may be assured of this, that the ambiguity of words, and the vague and improper application of them, have thrown more darkness upon this subject than the subtilty and intricacy of things.

When we use common words, we ought to use them in the sense in which they are most commonly used by the best and purest writers in the language; and, when we have occasion to enlarge or restrict the meaning of a common word, or give it more precision than it has in common language, the reader ought to have warning of this, otherwise we shall impose upon ourselves and upon him. A very respectable writer has given a good example of this kind, by explaining, in an Appendix to his "Elements of Criticism," the terms he has occasion to use. In that Appendix, most of the words are explained on which I have been making observations; and the explication I have given, I think, agrees, for the most part, with his.

Other words that need explication, shall be explained as they occur. [36]

conducts himself in the affairs of life. Of those principles, some are common to all men, being evident in themselves, and so necessary in the conduct of life that a man cannot live and act according to the rules of common prudence without them.

All men that have common understanding, agree in such principles; and consider a man as lunatic or destitute of common sense, who denies or calls them in question. Thus, if any man were found of so strange a turn as not to believe his own eyes, to put no trust in his senses, nor have the least regard to their testimony, would any man think it worth while to reason gravely with such a person, and, by argument, to convince him of his error? Surely no wise man would. For, before men can reason together, they must agree in first principles; and it is impossible to reason with a man who has no principles in common with you.

There are, therefore, common principles, which are the foundation of all reasoning and of all science. Such common principles seldom admit of direct proof, nor do they need it. Men need not to be taught them; for they are such as all men of [37] common understanding know; or such, at least, as they give a ready assent to, as soon as they are proposed and understood.

Such principles, when we have occasion to use them in science, are called axioms. And, although it be not absolutely neces sary, yet it may be of great use, to point out the principles or axioms on which a science is grounded.

Thus, mathematicians, before they prove any of the propositions of mathematics, lay down certain axioms, or common principles, upon which they build their reasonings. And although those axioms be truths which every man knew before-such as, That the whole is greater than a part, That equal quantities added to equal quantities make equal sums; yet, when we see nothing assumed in the proof of mathematical propositions, but such self-evident axioms, the propositions appear more certain, and leave no room for doubt or dispute.

In all other sciences, as well as in mathematics, it will be found that there are a few common principles, upon which all the reasonings in that science are grounded, and into which they may be resolved. If these were pointed out and considered, we should be better able to judge what stress may be laid upon the conclusions in that science. If the principles be certain, the conclusions justly drawn from them must be certain. If the principles be only probable, the conclusions can only be probable. If the prin ciples be false, dubious, or obscure, the superstructure that is built upon them must partake of the weakness of the foundation.

Sir Isaac Newton, the greatest of natural philosophers, has given an example well worthy of imitation, by laying down the common principles or axioms, on which the reasonings in natural philosophy are built. Before this was done, the reasonings of philosophers in that science were as vague and uncertain as they are in most others. Nothing was fixed; all was dispute and controversy; [38] but, by this happy expedient, a solid foundation is laid in that science, and a noble superstructure is raised upon it, about which there is now no more dispute or controversy among men of knowledge, than there is about the conclusions of mathematics.

It may, however be observed, that the first principles of natural philosophy are of a quite different nature from mathematical axioms: they have not the same kind of evidence, nor are they necessary truths, as mathematical axioms are. They are such as these: That similar effects proceed from the same or similar causes; That we ought to admit of no other causes of natural effects, but such as are true, and sufficient to account for the effects. These are principles which, though they have not the same kind of evidence that mathematical axioms have; yet have such evidence that every man of common understanding readily assents to them, and finds it absolutely necessary to conduct his actions and opinions by them, in the ordinary affairs of life.

Though it has not been usual, yet I conceive it may be useful, to point out some of those things which I shall take for granted, as first principles, in treating of the mind and its faculties. There is the more occasion for this; because very ingenious men, such as Des Cartes, Malebranche, Arnauld, Locke, and many others, have lost much labour, by not distinguishing things which require proof, from things which, though they may admit of illustratration, yet, being self-evident, do not admit of proof. When men attempt to deduce such self-evident principles from others more evident, they always fall into inconclusive reasoning: and the consequence of this has been, that others, such as Berkeley and Hume, finding the arguments brought to prove such first principles to be weak and inconclusive, have been tempted first to doubt of them, and afterwards to deny them.

It is so irksome to reason with those who deny first principles, that wise men commonly decline it. Yet it is not impossible, that [39] what is only a vulgar prejudice may be mistaken for a first principle. Nor is it impossible that what is really a first principle may, by the enchantment of words, have such a mist thrown about it, as to

hide its evidence, and to make a man of candour doubt of it. Such cases happen more frequently, perhaps, in this science than in any other; but they are not altogether without remedy. There are ways by which the evidence of first principles may be made more apparent when they are brought into dispute; but they require to be handled in a way peculiar to themselves. Their evidence is not demonstrative, but intuitive. They require not proof, but to be placed in a proper point of view. This will be shewn more fully in its proper place, and applied to those very principles which we now assume. In the meantime, when they are proposed as first principles, the reader is put on his guard, and warned to consider whether they have a just claim to that character.

1. First, then, I shall take it for granted, that I think, that I remember, that I reason, and, in general, that I really perform all those operations of mind of which I am conscious.

The operations of our minds are attended with consciousness; and this consciousness is the evidence, the only evidence, which we have or can have of their existence. If a man should take it into his head to think or to say that his consciousness may deceive him, and to require proof that it cannot, I know of no proof that can be given him; he must be left to himself, as a man that denies first principles, without which there can be no reasoning. Every man finds himself under a necessity of believing what consciousness testifies, and everything that hath this testimony is to be taken as a first principle.*

2. As by consciousness we know certainly the existence of our present thoughts and passions; so we know the past by remembrance.+ And, when they are recent, and the remembrance of them fresh, [40] the knowledge of them, from such distinct remembrance, is, in its certainty and evidence, next to that of conscious

attention is turned to the injury done him, or the injurious person; and he gives very little attention to the passion of anger, although he is conscious of it. It is in our power, however, when we come to the years of understanding, to give attention to our own thoughts and passions, and the various operations of our minds. And, when we make these the objects of our attention, either while they are present or when they are recent and fresh in our memory, this act of the mind is called reflec tion.

We take it for granted, therefore, that, by attentive reflection, a man may have a clear and certain knowledge of the operations of his own mind; a knowledge no less clear and certain than that which he has of an external object when it is set before his eyes.

This reflection is a kind of intuition, it gives a like conviction with regard to internal objects, or things in the mind, as the faculty of seeing gives with regard to objects of sight. A man must, therefore, be convinced beyond possibility of doubt, of everything with regard to the operations of his own mind, which he clearly and distinctly discerns by attentive reflection.

4. I take it for granted that all the thoughts I am conscious of, or remember, are the thoughts of one and the same thinking principle, which I call myself, or my mind. Every man has an immediate and irresistible conviction, not only of his present existence, but of his continued existence and identity, as far back as he can remember. If any man should think fit to demand [41] a proof that the thoughts he is successively conscious of, belong to one and the same thinking principle-if he should demand a proof that he is the same person to-day as he was yesterday, or a year ago I know no proof that can be given him he must be left to himself, either as a man that is lunatic, or as one who denies first principles, and is not to be | reasoned with.

Every man of a sound mind, finds himself under a necessity of believing his own identity, and continued existence. The conviction of this is immediate and irresist

able; and, if he should lose this conviction, it would be a certain proof of insanity, which is not to be remedied by reasoning.

5. I take it for granted, that there are some things which cannot exist by themselves, but must be in something else to which they belong, as qualities, or attributes. Thus, motion cannot exist, but in some

See infra, pp. 60, 105, 581, where a similar, and

pp. 324, 516, where a different extension is given to Reflection.

On Attention and Reflection, in the history of psychology, see Note 1.-H.

thing that is moved. And to suppose that there can be motion while everything is at rest, is a gross and palpable absurdity. In like manner, hardness and softness, sweetness and bitterness, are things which cannot exist by themselves; they are qualities of something which is hard or soft, sweet or bitter. That thing, whatever it be, of which they are qualities, is called their subject; and such qualities necessarily suppose a subject.

Things which may exist by themselves, and do not necessarily suppose the existence of anything else, are called substances; and, with relation to the qualities or attributes that belong to them, they are called the subjects of such qualities or attributes.

All the things which we immediately perceive by our senses, and all the things we are conscious of, are things which must be in something else, as their subject. Thus, by my senses, perceive figure, colour, hardness, softness, motion, resistance, and such [42] like things. But these are qualities, and must necessarily be in something that is figured, coloured, hard or soft, that moves, or resists. It is not to these qualities, but to that which is the subject of them, that we give the name of body. If any man should think fit to deny that these things are qualities, or that they require any subject, I leave him to enjoy his opinion as a man who denies first principles, and is not fit to be reasoned with. If he has common understanding, he will find that he cannot converse half an hour without say ing things which imply the contrary of what he professes to believe.

In like manner, the things I am conscious of, such as thought, reasoning, desire, necessarily suppose something that thinks, that reasons, that desires. We do not give the name of mind to thought, reason, or desire; but to that being which thinks, which reasons, and which desires.

That every act or operation, therefore, supposes an agent, that every quality sup poses a subject, are things which I do not attempt to prove, but take for granted. Every man of common understanding discerns this immediately, and cannot entertain the least doubt of it. In all languages, we find certain words which, by gramma rians, are called adjectives. Such words denote attributes, and every adjective must have a substantive to which it belongsthat is, every attribute must have a subject. In all languages, we find active verbs which denote some action or operation; and it is a fundamental rule in the grammar of all languages, that such a verb supposes a person-that is, in other words, that every action must have an agent. We take it, therefore, as a first principle. that goodness, wisdom, and virtue, can only be in some