study the laws of your own minds. Many pupils do not seem to understand that it is the powers and movements of the immaterial principle within their own bosoms, which are the objects of investigation in such a science. Because illustrations are drawn from the histories of men with strange names, who lived in other countries, and a half a century ago, they seem insensibly to imbibe the idea, that it is the philosophy of these men's minds which they are studying, not their own. Now the fact is, that appeals are made to the history and experience of these individuals, simply because they are more accessible to the writers of books. A perfect system of Intellectual Philosophy might be written, with all its illustrations drawn from the thoughts and feelings of any single pupil in the class. The mind is in its essential laws everywhere the same; and of course you can find the evidence of the existence and operation of all these laws in your own breasts, if you will look there. What you cannot, by proper research, find confirmed by your own experience, or your observations upon those around you, is not a law of mind.

Such is substantially the course which is recommended to those who shall commence the study of this work. It will be perceived that the object of it is to make the study of it, if possible, not what it too often is, the mere mechanical repetition of answers marked and committed to memory, but an intellectual and thorough investigation of a science. If the book is studied in this way, it must have a most powerful influence in cultivating accurate and discriminating habits, in developing intellectual power, and in storing the mind with facts of the most direct and practical importance, in all the connections of society, and in all the business of life.

Its true design. General object of this introduction.

INQUIRIES

CONCERNING THE

INTELLECTUAL POWERS, &c

PART I.

OF THE NATURE AND EXTENT OF OUR KNOWLEDGE OF MIND.

THE mind is that part of our being which thinks and wills, remembers and reasons: we know nothing of it except from these functions. By means of the corporeal senses it holds intercourse with the things of the external world, and receives impressions from them. But of this connection also we know nothing but the facts; when we attempt to speculate upon its nature and cause, we wander at once from the path of philosophical inquiry into conjectures which are as far beyond the proper sphere as they are beyond the reach of the human faculties. The object of true science on such a subject, therefore, is simply to investigate the facts, or the relations of phenomena, respecting the operations of mind itself, and the intercourse which it carries on with the things of the external world.

This important rule in the philosophy of mind has been fully recognised in very modern times only, so that the science, as a faithful interpretation of nature, may be considered as of recent origin. Before the period now referred to, the investigation was encumbered by the most fruitless speculations respecting the essence of mind, and other discussions which led to no discovery of truth. It was contended, for example, that the mind cannot act where it is

The mind-what? Its connection with the material world? Object of true science? In what sense is the science recent? Nature of former speculations.

not present, and that consequently it cannot be said to perceive external objects themselves, but only their images, forms, or sensible species, which were said to be conveyed through the senses, and represented to the mind in the same manner in which images are formed in a camera obscura. By the internal functions of mind these sensible species were then supposed to be refined into phantasms, the objects of memory and imagination; and these, after undergoing a further process, became intelligible species, the objects of pure intellect. By a very natural application of this doctrine, it was maintained by bishop Berkeley and the philosophers of his school, that as the mind can perceive nothing but its own impressions or images, we can derive no evidence from our senses of the existence of the external world; and Mr. Hume carried the argument a little further, by maintaining that we have as little proof of the existence of mind, and that nothing exists in the universe except impressions and ideas. Of another sect of philosophers who arose out of the same system, each individual professed to believe his own existence, but would not admit the existence of any other being; hence they received the appropriate name of Egotists.

The various eminent individuals by whom the fallacy of these speculations was exposed, combated them upon the principle that the doctrine of ideas is entirely a fiction of philosophers; and that a confidence in the information con veyed to us by our senses must be considered as a first truth, or a fundamental law of our nature, susceptible of no explanation, and admitting of no other evidence than that which is derived from the universal conviction of mankind. Nor does it, to common minds, appear a slight indication of the validity of this mode of reasoning, that the philosophers who supported this theory do not appear to have acted upon their own system; but in every thing which concerned their personal accommodation or personal safety, showed the same confidence in the evidence of their senses as other

men.

The deductions made from the ideal theory by Berkeley and Hume seem to have been applications of it which its for

Supposed process by which we become acquainted with external objects. Errors resulting. Berkeley's opinion? Hume's opinion? How refuted. Did these philosophers really believe their own system?

mer advocates had not contemplated. But it is a singular fact, as stated by Dr. Reid, that nearly all philosophers, from Plato to Mr. Hume, agree in maintaining that the mind does not perceive external things themselves, but only their ideas, images, or species. This doctrine was founded upon the maxim that mind cannot act where it is not present; and we find one writer only, who, admitting the maxim, called in question the application of it so far as to maintain that the mind, in perceiving external things, leaves the body, and comes into contact with the objects of its perception.

Such speculations ought to be entirely banished from the science of mind, as not only useless and unprofitable, but as referring to things entirely beyond the reach of the human faculties, and therefore contrary to the first principles of philosophical investigation. To the same class we are to refer all speculations in regard to the essence of mind, the manner in which thought is produced, and the means by which the intercourse is carried on between the mind and external objects. These remarkable functions were at one time explained by an imaginary essence called the animal spirits, which were supposed to be in constant motion, performing the office of messengers between the brain and the organs of sense. By another class of philosophers, of no very ancient date, thinking was ascribed to vibrations in the particles of the brain. The communication of perceptions from the senses to the mind has been accounted for in the same manner by the motions of the nervous fluid, by vibrations of the nerves, or by a subtile essence, resembling electricity or galvanism. The mind, again, has been compared to a camera obscura, to a mirror, and to a storehouse. In opposition, however, to all such hypotheses, which are equally incapable either of proof or of refutation, our duty is to keep steadily in view, that the objects of true science are facts alone, and the relations of these facts to each othThe mind can be compared to nothing in nature; it has been endowed by its Creator with a power of perceiving external things; but the manner in which it does so is entirely beyond our comprehension. All attempts, therefore,

er.

Dr. Reid's statement? Foundation of this doctrine. Author's opinion of such speculations? Theory of animal spirits. Theory of vibrations. Various other the

ories.

to explain or illustrate its operations by a reference to any thing else, can be considered only as vain and futile. They are endeavors to establish a resemblance where there is not a vestige of an analogy; and consequently they can lead to no useful result. It is only by a rigid adherence to this course of investigation that we can expect to make any progress in true knowledge, or to impart to our inquiries in any department of science the characters either of truth or utility.

The ideal theory, with all the doctrines founded upon it, may now be considered as gone by. But certain speculations are still occasionally brought out by writers of a particular order, which are referable to the same class, namely, hypotheses which are to be treated, not merely as unsound, but as being, by their very nature, directly opposed to the first principles of philosophical inquiry. Among these, the most prominent is the doctrine of materialism, of which it may be advisable to take a slight view in the commencement of this essay. On the principles which have been referred to, the following considerations may be submitted as bearing upon the subject.

The term matter is a name which we apply to a certain combination of properties, or to certain substances which are solid, extended, and divisible, and which are known to us only by these properties. The term mind, in the same manner, is a name which we apply to a certain combination of functions, or to a certain power which we feel within, which thinks, and wills, and reasons; and is known to us only by these functions. The former we know only by our senses, the latter only by our consciousness. In regard to their essence or occult qualities, we know quite as little about matter as we do about mind; and in as far as our utmost conception of them extends, we have no ground for believing that they have any thing in common.

It is highly important that the pupil should entertain clear ideas of the distinction between the essence and the properties of bodies. Take, for an example to illustrate this, an orange. It has a peculiar color. This color is one of its properties. Imagine this to be taken away. It has taste, which is another property. Remove this also.

Proper view of the nature of mind? Doctrine of materialism. Reason for alluding to it. Proper applications of the terms matter and mind? Distinction between essence and properties? Illustration.