It is, no doubt, perfectly true, that we all believe in the existence of matter, and that we all act up to this belief. But surely that statement is not a thing, to be put into a book and sold. It is not even a thing which one man is entitled to tell gratuitously to another man who knows it just as well as he does. It must be admitted upon a moment's reflection, that to communicate such information is to trifle with people's patience in an intolerable degree, is to trespass most abominably upon public or upon private indulgence. What, then, shall we say, when we find this kind of truth not only gravely imparted, but vehemently reiterated and enforced by scientific men, as it is in the pages of Dr Reid and other celebrated expounders of the philosophy of the human mind? We shall only say, that the economy of science is less understood than that of commerce; and that while material articles, such as air and sunshine, which are accessible to all, are for that reason excluded from the market of trade, many intellectual wares, which are at least equally accessible, are most preposterously permitted to have a place in the market of science. Such wares are the instinctive principles of Dr Reid. To inform a man that the material universe exists, and that he believes in its existence, is to take for granted that he is an idiot.
The circumstance which led the philosophers of Common Sense to traffic in this kind of article, was perhaps the notion that truths had a value in communication in proportion to their importance to mankind. But that is a most mistaken idea. The most important truths have absolutely no value in communication. The truth that "each of us exists"—the truth "that each of us is the same person to-day that he was yesterday," the truth that "a material universe exists, and that we believe in its existence,"—all these are most important truths—most important things to know. It is difficult to see how we could get on without this knowledge. Yet they are not worth one straw in communication. And why not? Just for the same reason that atmospheric air, though absolutely indispensable to our existence, has no value whatever in exchange—this reason being that we can get, and have already got, both the air and the truths, in unlimited abundance for nothing,—and thanks to no man. Why give a man what he has already got to his heart's content—why teach him what he already knows even to repletion?
It is not its importance, then, which confers upon truth its value in communication. In other words, it is a most superfluous civility for one man to impart truth to another, solely because it happens to be important. If the important truth be already perfectly well known to the recipient, and if the imparter of it is aware that the recipient knows it just as well as he does,—"thank you for nothing" is, we think, the mildest reply that could be made in the circumstances. The fact is, that the value of truth is measured by precisely the same standard which determines the value of wealth. This standard is in neither case the importance of the article,—it is always its difficulty of attainment,—its cost of production. Has labour been expended on its formation or acquisition; then the article, if a material commodity, has a value in exchange—if a truth, it has a value in communication. Has no labour been bestowed upon it, and has Nature herself furnished it to every human being in overflowing abundance, then the thing is altogether destitute of exchange-value—whether it be an article of matter or of mind. No man can, without impertinence, transmit or convey such a commodity to his neighbour.
If this be the law on the subject, (and we conceive that it must be so ruled) it settles the question as to the second mode of dealing with the problem of perception. It establishes the point that this method of treating the problem is not to be permitted. It is tabooed by the very nature of things. Air and sunshine are excellent and most important articles, but they are not things to carry to market in bottles,—because no labour is required to produce them, and because they are the gratuitous and abundant property of every living soul. In the same way, the existence
