Full Title: An Inquiry into the Human Mind, on the Principles of Common Sense. By Thomas Reid. Glasgow: Printed by W. Falconer, and sold by the booksellers, 1817.
[First published 1764].
TO
THE RIGHT HONOURABLE
JAMES, EARL OF FINDLATER AND SEAFIELD
CHANCELLOR OF THE UNIVERSITY OF OLD ABERDEEN
My Lord,
Though I apprehend that there are things new and of some importance, in the following inquiry, it is not without timidity that I have consented to the publicaiton of it. The subject has been canvassed by men of very great penetration and genius: for who does not acknowledge DES CARTES, MALEBRANCHE, LOCKE, BERKELEY, and HUME, to be such? A view of the human understanding, so different from that which they have exhibited, will, no doubt, be condemened by many without explanation, as proceeding from temerity and vanity.
BUT I hope the candid and discerning Few, who are capable of attending to the operations of their own minds, will weigh deliberately what is here advanced, before they pass sentence upon it. To such I appeal, as the only competent judges. If they disapprove, I am probably in the wrong, and shall be ready to change my opinion upon conviction. If they approve, the Many will at last yield to their authority, as they always do.
HOWEVER contrary my notions are to those of the writers I have mentioned, their speculations have been of great use to me, and seem even to point out the road which I have taken: and your Lordship knows, that the merit of useful discoveries is sometimes not more justly due to those that have hit upon them, than to others that have ripened them, and brought them to the birth.
I ACKNOWLEDGE, my Lord, that I never thought of calling in question the principles commonly received with regard to human understanding, until the Treatise of Human Nature was published in the year 1739. The ingenious author of that treatise, upon the principles of LOCKE, who was no sceptic, hath built a system of scepticism, which leaves no ground to believe any one thing rather than the contrary. His reasoning appeared to me to be just: there was therfore a necessity to call in question the principles upon which it was founded, or to admit the conclusion.
BUT can any ingenuous mind admit this sceptical system without reluctance? I truly could not, my Lord: for I am persuaded, that absolute scepticism is not more destructive of the faith of a Christian, than of the science of a philospher, and of the prudence of a man of common understanding. I am persuaded, that the unjust live by faith as well as the just; that, if all belief could be laid aside, piety, patriotism, friendship, parental affection, and private virtue, would appear as ridiculous as knight-errantry; and that the pursuits of pleasure, of ambition, and of avarice, must be grounded upon belief, as well as those that are honourable or virtuous.
THE day-labourer toils at his work, in the belief that he shall receive his wages at night; and if he had not this belief he would not toil. We may venture to say, that even the author of this sceptical system, wrote it in the belief that it should be read and regarded. I hope he wrote it in the belief also, that it would be useful to mankind: and perhaps it may prove so at last. For I conceive the sceptical writers to be a set of men, whose business is to pick holes in the fabric of knowledge wherever it is weak and faulty; and when these places are properly repaired, the whole building becomes more firm and solid than it was formerly.
FOR my own satisfaction, I entered into a serious examination of the principles upon which this sceptical system is built; and was not a little surprised to find, that, it leans with its whole weight upon a hypothesis, which is ancient indeed, and hath been very generally received by philosophers, but of which I could find no solid proof. The hypothesis I mean, is, That nothing is perceived but what is in the mind which perceives it: That we do not really perceive things that are external, but only certain images and pictures of them imprinted upon the mind, which are called impressions and ideas.
IF this be true; supposing certain impressions and ideas to exist in my mind, I cannot, from their existence, infer the existence of any thing else: my impressions and ideas are the only existences of which I can have any knowledge or conception; and they are such fleeting and transitory beings, that they can have no existence at all, any longer than I am conscious of them. So that, upon this hypothesis, the whole universe about me, bodies and spirits, sun, moon, stars, and earth, friends and relations, all things without exception, which I imagined to have permanent existence, whether I thought of them or not, vanish at once;
And, like the baseless fabric of a vision,
Leave not a track behind.
I THOUGHT it unreasonable, my Lord, upon the authority of philosophers, to admit a hypothesis, which, in my opinion, overturns all philosophy, all religion and virtue, and all common sense: and finding that all the systems concerning the human understanding which I was acquainted with, were built upon this hypothesis, I resolved to inquire into this subject anew, without regard to any hypothesis.
WHAT I now humbly present to your Lordship, is the fruit of this inquiry, so far only as it regards the five senses; in which I claim no other merit, than that of having given great attention to the operations of my own mind, and of having expressed, with all the perspicuity I was able, what I conceive every man, who gives the same attention, will feel and perceive. The productions of imagination, require a genius which soars above the common rank; but the treasures of knowledge are commonly buried deep, and may be reached by those drudges who can dig with labour and patience, though they have not wings to fly. The experiments that were to be made in this investigation suited me, as they required no other expence, but that of time and attention, which I could bestow. The leisure of an academical life, disengaged from the pursuits of interest and ambition; the duty of my profession, which obliged me to give prelections on these subjects to the youth; and an early inclination to speculations of this kind, –have enabled me, as I flatter myself, to give a more minute attention to the subject of this inquiry, than has been given before.
MY thoughts upon this subject were, a good many years ago, put together in another form, for the use of my pupils, and afterwards were submitted to the judgment of a private philosophical society, of which I have the honour to be a member. A great part of this inquiry was honoured even by your Lordship’s perusal. And the encouragement which you, my Lord, and others, whose friendship is my boast, and whose judgment I reverence, were pleased to give me, counterbalance my timidity and diffidence, and determined me to offer it to the public.
IF it appears to your Lordship to justify the common sense and reason of mankind, against the sceptical subtilties which, in this age, have endeavoured to put them out of countenance; if it appears to throw any new light upon one of the noblest parts of the divine workmanship; your Lordship’s respect for the arts and sciences, and your attention to every thing which tends to the improvement of them, as well as to every thing else that contributes to the felicity of your country, leave me no room to doubt of your favourable acceptance of this essay, as the fruit of my industry in a profession wherein I was accountable to your Lordship; and as a testimony of the great esteem and respect wherewith I have the honour to be,
My Lord,
Your Lordship’s most obliged,
and most devoted servant,
Tho. Reid.
Eighteenth-Century Reading Room 