seen by human eye, and shrinks from the anticipation of a reckoning to come, each has forced upon him a conviction, such as argument never gave, that the being which is essentially himself is distinct from any function of the body, and will survive in undiminished vigour when the body shall have fallen into decay.

When, indeed, we take into the inquiry the high principles of moral obligation, and the moral government of the Deity, this important truth is entirely independent of all our feeble speculations on the essence of mind. For though we were to suppose, with the materialist, that the rational soul of man is a mere chymical combination, which, by the dissolution of its elements, is dissipated to the four winds of heaven, where is the improbability that the Power which framed the wondrous compound may collect these elements again, and combine them anew, for the great purposes of his moral administration. In our speculations on such a momentous subject we are too apt to be influenced by our conceptions of the powers and properties of physical things; but there is a point where this principle must be abandoned, and where the soundest philosophy requires that we take along with us a full recognisance of the power of God.

The

There is thus, in the consciousness of every man, a deep impression of continued existence. casuist may reason against it till he bewilder himself in his own sophistries; but a voice within gives the lie to his vain speculations, and pleads with authority for a life which is to come. The sincere and humble inquirer cherishes the impression, while he seeks for farther light on a subject so momentous; and he thus receives, with absolute conviction, the truth which beams upon him from the revelation of God, that the mysterious part of his being, which thinks, and wills, and reasons, shall indeed survive the wreck of its mortal tenement, and is destined for immortality.

PART II.

OF THE ORIGIN OF OUR KNOWLEDGE OF FACTS RELATING BOTH TO MIND AND MATTER.

AMONG writers on the science of mind, there was formerly much controversy in regard to the origin of our ideas. Some maintained that they are derived entirely from perception, that is, through the external senses; others considered them as arising partly from perception and partly from consciousness, or reflection; and some added a third class, which they called innate ideas, and which were supposed to exist in the mind itself, independently of and prior to the exercise either of perception or reflection. This phraseology had its origin in the ancient theory of ideas, according to which something was supposed to exist distinct both from the mind and the external object of its perception. This, as we have formerly seen, was what philosophers meant by an idea. It was believed to be the immediate object of the mind's perception, but to be only a kind of image or representative of the object perceived. This hypothesis, which kept its place in the science of mind till a very recent period, is now generally admitted to have been a fiction of philosophers; and the phraseology respecting ideas is abandoned by the best practical writers; because, though the ancient doctrine be exploded, and the term may be used only in a figurative sense, it still seems to imply something existing in the mind distinct from the mind itself. The impressions derived from external things are therefore to be considered as the occasions on which

the various powers of the mind are brought into action. These powers themselves then become the objects of consciousness or reflection, and by their further exercise we acquire certain notions which arise out of the mental operations. This doctrine gives no encouragement to the scheme of materialism, for it is clear that we cannot remember till we are furnished with some fact to be remembered; but this can never be supposed to affect our belief in the existence of the power of memory before the fact was so furnished. If we could suppose the case of a man who had lived all his life in the dark, he certainly could not see, but we should not say that the admission of light imparted to him the power of vision; it only furnished the circumstances which gave occasion to the exercise of sight. It has accordingly been shown by Mr. Stewart, that though we may not be conscious of our mental powers till they are called into action, yet this may arise from the most simple sensation,-such as affords no evidence of the properties, or even of the existence of the material world.

Through the senses, then, we acquire a knowledge of the facts relating to external things. The mental processes thus brought into action then become the subjects of consciousness, and we acquire a knowledge of the facts relating to them. By a further exercise of these powers on various facts referring to both matter and mind, we acquire certain notions arising out of our reflection upon the relations of these facts, such as our notions of time, motion, number, cause and effect, and personal identity; and we acquire, further, the impression of certain fundamental laws of belief, which are not referable to any process of reasoning, but are to be considered as a part of our constitution, or a spontaneous and instinctive exercise of reason in every sound mind.

The origin of our knowledge then is referable, in a philosophical point of view, to perception and

reflection. But, in point of fact, the knowledge which is acquired by an individual through his own perception and reflection is but a small part of what he possesses; much of the knowledge possessed by every one is acquired through the perceptions of other men. In an essay, therefore, which is intended to be entirely practical, I shall include this last department under the head of Testimony. The division of this part of the subject will therefore be, 1. Sensation and Perception.

2. Consciousness and Reflection.
3. Testimony.

SECTION I.

OF SENSATION AND PERCEPTION.

We know nothing of perception except the fact that certain impressions made upon the organs of sense convey to the mind a knowledge of the properties of external things. Some of the older speculations on this subject have already been referred to. In these the mind was compared to a camera obscura, and the transmission of the forms or images of things to it from the organs of sense was explained by the motion of the animal spirits, or the nervous fluid, or by vibrations in the substance of the nerves. All such speculations are now dismissed from the investigation, being considered as attempts to penetrate into mysteries which are beyond the reach of the human faculties, and consequently not the legitimate objects of philosophical inquiry.

Our first knowledge of the existence and properties of the material world is evidently of a complex

nature. It seems to arise from the combined action of several senses, conveying to us the general notion of certain essences which are solid and extended, or possessed of those properties which characterize material things. Without this general knowledge previously acquired, our various senses acting individually could convey to us no definite notion of the properties of external things. A smell, that is, a mere odour, for example, might be perceived by us, but would convey nothing more than the sensation simply. It could not communicate the impression of this being a property of an external body, until we had previously acquired a knowledge of the existence of that body, and had come by observation to associate the sensation with the body from which it proceeds. The same holds true of the other senses, and we are thus led at the very first step of our inquiry to a complicated process of mind without which our mere sensations could convey to us no definite knowledge.

Having thus acquired a knowledge of the existence and general properties of material things, we next derive from our various senses a knowledge of their more minute characters. These are generally divided into primary and secondary. The primary qualities of material things are such as are essential, and must at all times belong to matter; such as solidity and extension. These properties necessarily convey to us a conviction of something existing out of the mind, and distinct from its own sensations. The secondary qualities, again, are colour, temperature, smell, taste, &c. These are not essential properties of matter, but qualities producing sensations in a sentient being; they may or they may not belong to any particular body, or they may be attached to it at one time and not at another. Hence they convey to us primarily no definite notion in regard to the existence or properties of external things, except, as Mr. Stewart expresses it,