on the one hand, nor to the reasoning power on the other, to an internal or mental suggestion as follows.-"I beg leave to make use of the word SUGGESTION, because I know not one more proper, to express a power of the mind which seems entirely to have escaped the notice of philosophers, and to which we owe many of our simple notions which are nether impressions nor ideas, as well as many original principles of belief. I shall endeavour

to illustrate, by an example, what I understand by this word. We all know that a certain kind of sound suggests immediately to the mind, a coach passing in the street; and not only produces the imagination, but the belief, that a coach is passing. Yet there is here no comparing of ideas no perception of agreements or disagreements, to produce this belief: nor is there the least similitude between the sound we hear, and the coach we imagine and believe to be passing.

"It is true that this suggestion is not natural and original; it is the result of experience and habit. But I think it appears, from what hath been said, that there are natural suggestions; particularly, that sensation suggests the notion of present existence, and the belief that what we perceive or feel, does now exist; that memory suggests the notion of past existence, and the belief that what we remember did exist in time past; and that our sensations and thoughts do also suggest the notion of a mind, and the belief of its existence, and of its relation to our thoughts. By a like natural principle it is, that a beginning of existence, or any change in nature suggests to us the notionof a cause, and compels our belief of its existence. And in like manner, as shall be shown when we come to the sense of touch, certain sensations of touch, by the constitution of our nature, suggest to us extension, solidity, and motion, which are nowise like to sensations, although they have hitherto been confounded with them."We find similar sentiments of this learned and cautious writer in various other places.

Mr. Stewart also in his Philosophical Essays, speaks of certain mental phenomena, as attendant upon the ob

jects of our consciousness, and as SUGGESTED by them. The notions of time, number, motion, memory, sameness, personal identity, present existence, &c. he ascribes neither to the external world on the one hand, nor to the internal mental operations, of which we are conscious on the other; except so far as they are the occasions, on which the mind brings them out, or SUGGESTS them from its own inherent energy. Of the notion of DURATION for instance, he would say, I do not see it, nor hear it, nor feel it, nor become acquainted with it by means of any other of the senses; nor am I conscious of it, as I am of believing, reasoning, and imagining, &c. but it is SUGGESTED by the mind itself; it is an intimation absolutely essential to the mind's nature and action.

It will be noticed that Dr. Reid has not limited the use of the word suggestion, exclusively to those cases, which are purely internal. Nor was this necessary. Those cases, however, where suggestion is brought into exercise by - occasions chiefly external, (as for instance, in forming the notion of outness or externality,) are few in number, and naturally and almost necessarily come up for consideration in treating of the separate senses. As a general statement, the occasions of its exercise are either wholly of an interiour nature, or with only a slight mixture of outward circumstances.

§. 200. Ideas of existence, mind, self-existence, and personal identity.

We shall now mention a few ideas, which have this origin, without undertaking to give a complete enumeration of them.

I.-EXISTENCE. Among the various notions, the origin of which naturally requires to be considered under the head of Suggestion, is that of existence. What existence is in itself, (that is to say independently of any existent being,) it would be useless to inquire. Using the word as expressive of a mental state, it is the name of a purely simple idea, and cannot be defined. The history

of its rise is briefly this. Such is our nature, that we

cannot exist, without having the notion of existence. Its origin is inseparable from the mere fact, that we have thought, feeling, and judgment.

II,-MIND. The origin of the notion of mind is similar to that of existence. Neither of them can be strictly and properly referred to the senses. We do not see the mind, nor is it an object of touch, nor of any other sense. Nor, on the other hand, is the notion of mind a direct object of the memory, or of reasoning, or of imagination. The notion arises naturally, or is suggested from the mere fact, that the mind actually exists and is susceptible of various feelings and operations.

III,-Similar remarks will apply to the notions, (whether we consider them as simple or complex,) of SELF-EXISTENCE and PERSONAL IDENTITY. At the very earliest period they flow out, as it were, from the mind itself; not resulting from any prolonged and laborious process, but freely and spontaneously suggested by it. This is so true, that no one is able to designate either the precise time, or the precise circumstances, under which they originate; for they spring into being under all circumstances. We cannot look, or touch, or breathe, or move, or think without them. These are riches of our inental nature too essential and important to be withheld, or to be given only on rare and doubtful occasions; but are spread abroad in all time and place, in all action and feeling.(See, in connection with this section, §. §. 17, 18, 19.)

§. 261. Of the nature of unity and the origin of that notion.

Another important notion, properly entitled to a consideration here, is that of UNITY. We shall decline attempting to explain the nature of unity, for the simple reason that nothing is more easy to be understood; every child knows what is meant by One. And how can we explain it, if we would? We can explain a hundred by resolving it into its parts; we can explain fifty or a score by making a like separation of the whole number into the subordinate portions, of which it is made up; but when we arrive at unity, we must stop, and can go no further.

It is true attempts have been made to define it, but like many other such attempts, they have proved futile. Unity has been called a thing indivisible in itself, and divided from every thing else. But this makes us no wiser. Is it any thing more than to say, that the unity of an object is its indivisibility? Or in other words that its unity is its unity?

As the idea of unity is one of the simplest, so it is one of the earliest notions which men have. It originates in the same way, and very nearly at the same time with the notions of existence, self-existence, personal identity, and the like. When a man has a notion of himself, he evidently does not think of himself as two, three, or a dozen men, but as one. As soon as he is able to think of himself as distinct from his neighbour, as soon as he is in no danger of mingling and confounding his own identity with that of the multitude around him, so soon does he form the notion of unity. It exists as distinct in his mind, as the idea of his own existence does; and arises there im. mediately successive to that idea, because it is impossible, in the nature of things, that he should have a notion of himself as a twofold or divided person.

Unity is the fundamental element of all enumeration. By the repetition or adding of this element, we are able to form numbers to any extent. These numbers may be combined among themselves, and employed merely as expressive of mutual relation; or we may apply them, if we choose, to all external objects whatever, to which we are able to give a common name. (See §. 233.).

§. 262. Nature of succession, and origin of the idea of

succession.

Another of those conceptions, which naturally offer themselves to our notice here, is that of SUCCESSION. This term, (when we inquire what succession is in itself,) is one of general application, expressive of a mode of existence rather than of existence itself; and in its application to mind in particular, expressive of a condition of the mind's action, but not of the action itself, which that

condition regulates. It is certainly a fact too well known to require comment, that our minds exist at different periods in successive states; that our thoughts and feelings, in obedience to a permanent law, follow each other in a train. This is the simple fact. And the fact of such succession, whenever it takes place, forms the occasion, on which the notion or idea of succession is SUGGESTED to the mind. Being a simple mental state, it is not susceptible of definition; yet every man possesses it, and every one is rightly supposed to understand its nature.

Accordingly it is not necessary to refer the origin of this idea to any thing external. It is certain, that the sense of smell cannot directly give us the idea of succession, nor the sense of taste, nor of touch. And we well know, that the deaf and dumb possess it, not less than others. The blind also, who have never seen the face of heaven, nor beheld that sun and moon, which measure out for us days and months and years, have the notion of succession. They feel, they think, they reason, at least in some small degree, like other men; and it is impossible, that they should be without it. The origin, therefore, of this notion is within; it is the unfailing result of the inward operation to call it forth, however true it may be that it is subsequently applied to outward objects and events.

§. 263. Origin of the notion of duration.

There is usually understood to be a distinction between the idea of succession, and that of duration, though neither can be defined. The idea of succession is supposed to be antecedent in point of time to that of duration; (we speak now of succession and duration relatively to our conception of them, and not in themselves considered.) Duration must be supposed to exist antecedently to succession in the order of nature; but succession is the form, in which it is made to apply to men; and is, therefore, naturally the occasion, on which the idea of it arises in men's minds. Having the notion of succession, and that of personal or self-existence, a foundation is laid for the addi