keeping constantly in view, the close and inseparable connection which will be afterwards shown to exist between the two different intellectual operations which are thus brought into immedi

ate contrast.

Opinions of the ancients respecting the argument from universul consent.· "Those things are to be regarded as first truths, [says Aristotle,] the credit of which is not derived from other truths, but is inherent in themselves. As for probable truths, they are such as are admitted by all men, or by the generality of men, or by wise men; and, among these last, either by all the wise, or by the generality of the wise, or by such of the wise as are of the highest authority."

The argument from Universal Consent, on which so much stress is laid by many of the ancients, is the same doctrine with the foregoing, under a form somewhat different. It is stated with great simplicity and force by a Platonic philosopher, [Maximus Tyrius,] in the following sentences:

"In such a contest, and tumult, and disagreement, (about other matters of opinion,) you may see this one law and language acknowledged by common accord. This the Greek says, and this the barbarian says; and the inhabitant of the continent, and the islander; and the wise, and the unwise.”

Objection to which the argument is liable. It cannot be denied, that against this summary species of logic, when employed without any collateral lights, as an infallible touchstone of philosophical truth, a strong objection immediately occurs. By what test, it may be asked, is a principle of common sense to be distinguished from one of those prejudices to which the whole human race are irresistibly led, in the first instance, by the very constitution of their nature? If no test or criterion of truth can be pointed out but universal consent, may not all those errors which Bacon has called idola tribus,* claim a

* [Idols of the Tribe, as they are called in the fanciful nomenclature of Lord Bacon, are the errors and prejudices to which all men (the whole tribe) are liable, because they grow out of the natural imperfections and biases of the human understanding. "For the light of the human intel

right to admission among the incontrovertible maxims of science? And might not the popular cavils against the supposition of the earth's motion, which so long obstructed the progress of the Copernican system have been legitimately opposed, as a reply of paramount authority, to all the scientific reasonings by which it was supported?

Criteria of First Truths.—It is much to be wished that this objection, of which Dr. Reid could not fail to be fully aware, had been more particularly examined and discussed in some of his publications, than he seems to have thought necessary. From different parts of his works, however, various important hints towards a satisfactory answer to it might be easily collected. At present, I shall only remark, that although universality of belief is one of the tests by which, according to him, a principle of common sense is characterized, it is not the only test which he represents as essential. Long before his time, Father Buffier, in his excellent treatise on First Truths, had laid great stress on two other circumstances, as criteria to be attended to on such occasions; and although I do not recollect any passage in Reid where they are so explicitly stated, yet the general spirit of his reasonings plainly shows, that he had them constantly in view, in all the practical applications of his doctrine. The first criterion mentioned by Buffier is, "That the truths assumed as maxims of common sense should be such, that it is impossible for any disputant either to defend or to attack them, but by means of propositions which are neither more manifest nor more certain than the propositions in question." The

lect," says Lord Bacon, "is not dry light; but it receives diverse stains and hues from the will and the affections, and thus creates such sciences as it longs for; for it readily believes what it wishes to be true." And again, "It is wrong to say, that the senses are the proper measures of things; for all our perceptions, whether of sense or of the intellect, conform rather to the nature of the observer, than to the nature of the thing observed. The human mind is like a mirror imperfectly polished and inaccurately shaped, which imparts its own qualities to the objects reflected in it, distorting and staining them."-Nov. Organum, Aph. XLI. and XLIX. paraphrased.]

second criterion is, "That their practical influence should extend even to those individuals who affect to dispute their authority."

To these remarks of Buffier, it may not be altogether superfluous to add, that, wherever a prejudice is found to obtain universally among mankind in any stage of society, this prejudice must have some foundation in the general principles of our nature, and must proceed upon some truth or fact inaccurately apprehended or erroneously applied. The suspense of judgment, therefore, which is proper with respect to particular opinions, till they be once fairly examined, can never justify scepticism with respect to the general laws of the human mind. Our belief of the sun's motion, is not a conclusion to which we are necessarily led by any such law, but an inference rashly drawn from the perceptions of sense, which do not warrant such an inference. All that we see is, that a relative change of position between us and the sun takes place; and this fact, which is made known to us by our senses, no subsequent discovery of philosophy pretends to disprove. It is not, therefore, the evidence of perception which is overturned by the Copernican system, but a judgment or inference of the understanding, of the rashness of which every person must be fully sensible, the moment he is made to reflect with due attention on the circumstances of the case; and the doctrine which this system substitutes, instead of our first crude apprehensions on the subject, is founded, not on any process of reasoning à priori, but on the demonstrable inconsistency of these apprehensions with the various phenomena which our perceptions present to us. Had Copernicus not only asserted the stability of the sun, but, with some of the Sophists of old, denied that any such thing as motion exists in the universe, his theory would have been precisely analogous to that of the non-existence of matter; and no answer to it could have been thought of more pertinent and philosophical, than that which Plato is said to have given to the same paradox in the mouth of Zeno, by rising up and walking before his eyes.

CHAPTER IX.

OF REASONING AND OF DEDUCTIVE EVIDENCE.

I. Doubts with respect to Locke's distinction between the powers of intuition and reasoning. Although, in treating of this branch of the philosophy of the mind, I have followed the example of preceding writers, so far as to speak of intuition and reasoning as two different faculties of the understanding, I am by no means satisfied that there exists between them that radical distinction which is commonly apprehended. Dr. Beattie, in his Essay on Truth, has attempted to show, that, how closely soever they may in general be connected, yet that this connection is not necessary; insomuch that a being may be conceived endued with the one, and at the same time destitute of the other. Something of this kind, he remarks, takes place in dreams and in madness; in both of which states of the system, the power of reasoning appears occasionally to be retained in no inconsiderable degree, while the power of intuition is suspended or lost.* But this doctrine is liable to obvious and to insurmountable objections; and has plainly taken its rise from the vagueness of the phrase common sense, which the author employs, through the whole of his argument, as synonymous with the power of intuition. Of the indissoluble connection between the last power

* [Locke very acutely observes, that the difference between an idiot and a madman consists in this;—that a madman reasons correctly from wrong premises, while an idiot does not reason at all. Thus you shall find a distracted man fancying himself a king, and, with a right inference, requiring suitable attendance, respect, and obedience; others, who have thought themselves made of glass, have used the caution necessary to preserve such brittle bodies." Now the wrong premises that the madman adopts are often false sensations, as the medical men call them; as when one

and that of reasoning, no other proof is necessary than the following consideration, that, "in every step which reason makes in demonstrative knowledge, there must be intuitive certainty ;" a proposition which Locke has excellently illustrated, and which, since his time, has been acquiesced in, so far as I know, by philosophers of all descriptions. From this proposition (which, when properly interpreted, appears to me to be perfectly just) it obviously follows, that the power of reasoning presupposes the power of intuition; and, therefore, the only question about which any doubt can be entertained is, whether the power of intuition (according to Locke's idea of it) does not also imply that of reasoning? My own opinion is, decidedly, that it does; at least, when combined with the faculty of memory. In examining those processes of thought which conduct the mind by a series of consequences from premises to a conclusion, I can detect no intellectual act whatever, which the joint operation of intuition and of memory does not sufficiently explain.

Reasoning resolved into intuition and memory. — Before, however, proceeding further in this discussion, it is proper for me to observe, by way of comment on the proposition just quoted from Locke, that, although "in a complete demonstration, there must be intuitive evidence at every step," it is not to be supposed that, in every demonstration, all the various intuitive judgments leading to the conclusion are actually presented to our thoughts. In by far the greater number of instances, we trust entirely to judgments resting upon the evidence of memory; by the help of which faculty, we are enabled to connect together the most remote truths, with the very same confidence as if the one were an immediate consequence of the other. Nor does this diminish,

fancies that he hears voices in the air, or sees spectres, the voices and the sights being alike unreal. These imaginary perceptions would be denominated by Kant false intuitions; and if this be a proper use of language, Beattie properly distinguishes intuition from reasoning, when he affirms that we can conceive of a being endued with the one, and destitute of the other. An insane person is such a being; he reasons rightly, but his intuitive faculty is perverted. But Stewart here understands intuition to be, not a perception, but an instantaneous judgment.]