use them with entire accuracy. Thus we speak of cause and effect, number, and various other ideas. When, however, we attempt to dwell upon any one of these ideas, so far as I can observe, we form a concept of it in the mind. Thus, when I think of the term horse as a genus, and dwell upon it in thought, there is before me, as an object, a concept of such an animal. So, if I think the axiom the whole is greater than its part, two magnitudes corresponding to these terms present themselves before me. From this remark, however, must be excepted those cases in which we recognize a truth as a necessary condition of thought, as duration, space, and ideas of a similar character. Even here, however, we find the mind from its natural impulse striving to realize something which shall correspond to a concept. Of conceptions thus explained it may be remarked in general: 1. In conception there is nothing numerically distinct from the act of the mind itself. From the analogies of language we are liable to be misled in thinking of this subject. We speak of forming a conception, and of forming a machine; of separating the elements of a conception, and of separating the parts of an object from one another. As in the one case there is some object distinct from the ego, we are prone to suppose that there must be also in the other. There is, however, in conception nothing but the act of the mind itself. We may, nevertheless, contemplate this act from different points of view; first, as an act of the mind, or as the mind in this particular act, and, secondly, as a product of that act which we use in thinking. There is, however, numerically nothing but the act of the mind itself. 2. Conception enters into all the other acts of the mind. In the simplest sensation there is, for the time being, a knowledge or a notion, though it may remain with us not a moment after the object producing it is withdrawn. We can have a knowledge of our own powers only as we have conceptions of them. We can remember, or judge, or reason, only as we have conceptions. In fact, all our mental processes are about conceptions. Of them, all our knowledge consists. 3. Our conceptions are to us the measure of possibility. When any proposition cannot be conceived, that is, is unthinkable, we declare it impossible or absurd. Thus, if it be said that a part is greater than the whole, that two straight lines can enclose space, or that a change can take place in a body while all the conditions of its existence remain absolutely the same, I understand the assertion; but when I attempt to form a conception of it, that is, to think it, I find myself unable to do so. I affirm it to be impossible. On the other hand, I may think of a communication between the earth and the moon. In the present state of science it is impracticable, but it is within the limits of thought, and my mind is not so organized that I feel it to be impossible. This case, is, however, to be distinguished from the unconditional, the incomprehensible. This, from the nature of our intellect, we know to be necessary; it is not contradictory to thought, though to grasp the conception is impossible. In the other case we are able to comprehend the terms, but we are unable to construe them in thought; in other words, the relation which is affirmed is unthinkable. 4. In simple conception, or where it is unattended by any other act of the mind, there is neither truth nor falsehood. I may conceive of a red mountain, of a blue rose, of a winged horse, but the conception has nothing to do with my belief in the existence of either of these objects. If the conception is united with an act of judgment or memory, then it at once becomes either true or false. In the concep tion itself, however, I can discover neither. Stewart, I know, advances a contrary opinion; but I must confess myself wholly unconvinced by his reasoning. 5. Conceptions may be either clear and distinct, or obscure and indistinct. We easily observe the difference here spoken of in the effects produced on us by different descriptions. Some authors describe a scene with so graphic a power that we at once form a conception as definite as though we had ourselves beheld it. Others use emphatic and imposing language, but they leave on us no distinct impression. We are deluged by a shower of words, but no conception is imprinted on the memory. 6. Conceptions may be strong and vivid, or faint and languid. The same scene may with equal faithfulness be described to us by two persons. The one deeply affects us, while the other hardly interests us sufficiently to command our continued attention. We observe the same effect in ourselves, resulting from the accidental tone of our own minds. At some times we find our conceptions much stronger than at others, under precisely the same external circumstances. From what has been observed, it will readily appear that the power of forming conceptions differs greatly in different individuals. Every teacher must have remarked this fact, in his attempts to communicate instruction. Some persons will at once seize upon the salient points of a conception, discover its bearing and relations, and hold it steadily before the mind, until it becomes incorporated with their knowledge. They never can be satisfied until they have attained to this result. Others require repeated explanations, and, when they suppose themselves to have mastered a conception, we are surprised to observe that no important point seems to have arrested their attention, but that there rest on their minds only considerations of inferior importance blended together in dim and uncertain confusion. The difference, in this respect, is still more remarkable in the connection of conception with the fine arts, though perhaps this exercise of the power belongs rather to the imagination. A portrait-painter will form so distinct a conception of a countenance that, years afterward, he will represent it correctly on canvas. The same power of forming distinct conceptions is essential to the poet or novelist. No one can read the descriptions of Sir Walter Scott without being sensible of his high endowment in this respect. Nor was this power limited to the scenes which he himself had witnessed. His description of a summer day in the deserts of Syria could not have been surpassed by the most gifted Bedouin Arab. It was to this power that he owed much of that brilliant conversational eminence, which rendered him the centre of attraction in every circle in which he chose to unbend himself. REFERENCES. Conception-Reid, Essay 1, chap. 1 Formed at will— Reid, Essay 4, chap. 1. Enter into every other act of the mind-Reid, Essay 4, chap. 1. Ingredients derived from other powers-Reid, Essay 4, chap. 1. Conception in general - Stewart, vol. i., chap. 3. Attended with belief- Stewart, vol. i., chap. 3. Power of description depends on — Stewart, vol. i., chap. 3. Stewart, vol. i., chap. 3. Conception-Abercrombie, Part 3, sect. 1. In conception neither truth nor falsehood — Locke, Book 2d, chap. 22, sects. 1-4, 19, 20. Clear or obscure - Locke, Book 2, ch. 29, sect. 1. 10 CHAPTER II. CONSCIOUSNESS, ATTENTION, AND REFLECTION. SECTION I. CONSCIOUSNESS. CONSCIOUSNESS is that condition of the mind in which it is cognizant of its own operations. It is not thinking and feeling, but that condition in which we know that we think or feel. Thought, however, is necessary to consciousness, for unless thought existed, we could not be conscious of it. We may nevertheless suppose a mental act to be performed of which we have no consciousness. In such a case we should have no knowledge of its present existence, and should only know that it had existed by its results. On this subject, however, a considerable diversity of opinion obtains. Sir W. Hamilton and many philosophers of the highest authority believe that consciousness cannot properly be separated from the act to whose existence it testifies, and that to make a distinction between the assertions, "I perceive" and "I am conscious of perception," is impossible. They hold that when we are not conscious of an act, the act is not performed; and that when consciousness does not testify to anything, it is because there is nothing concerning which it can testify. In answer to this, it may be granted that when it is said "I perceive," the meaning is the same as when I say "I am conscious of perceiving." When I say "I perceive," |