On the same page, he remarks:— “In saying (to use the words of Aristotle) simply and without qualification, that this or that is a known truth, we do not mean that it is in fact recognized by all, but only by such as are of a sound understanding; just as, in saying absolutely that a thing is wholesome, we must be held to mean, to such as are of a hale constitution.� The passage of Aristotle’s Topica here noticed will be found to have a different bearing from that which Hamilton gives it.
Aristotle is laying down (Topica, VI. iv. p. 141, a. 23-p. 142, a. 16) the various lines of argument which may be followed out, when you are testing in dialectical debate a definition given or admitted by the opponent. There cannot be more than one definition of the same thing: the definition ought to declare the essence of the thing, which can only be done by means of priora and notiora. But notiora admits of two meanings: (1) notiora simpliciter; (2) notiora nobis or singulis hominibus. Under the first head, that which is prius is absolutely more knowable than that which is posterius; thus, a point more than a line, a line more than a plane, a plane more than a solid. But under the second head this order is often reversed: to most men the solid (as falling more under sense) is more knowable than the plane, the plane than the line, the line than the point. The first (notiora simpliciter) is the truly scientific order, suited to superior and accurate minds, employed in teaching, learning, and demonstration (p. 141, a. 29: καθάπερ ἐν ταῖς ἀποδείξεσιν, οὕτω γὰρ πᾶσα διδασκαλία καὶ μάθησις ἔχει, — b. 16: ἐπιστημονικώτερον γὰρ τὸ τοιοῦτόν ἐστιν). The second (notiora nobis) is adapted to ordinary minds, who cannot endure regular teaching, nor understand a definition founded on the first order. But definitions founded on the second alone (Aristotle says) are not satisfactory, nor do they reveal the true essence of the thing defined: there can be no satisfactory definition unless what is notius simpliciter coincides with what is notius nobis (p. 141, b. 24). He then proceeds to explain what is meant by notius simpliciter; and this is the passage quoted by Hamilton. After having said that the notiora nobis are not fixed and uniform, but vary with different individuals, and even in the same individual at different times, he goes on: “It is plain therefore that we ought not to define by such characteristics as these (the notiora nobis), but by the notiora simpliciter: for it is only in this way that we can obtain a definition one and the same at all times. Perhaps, too, the notius simpliciter is not that which is knowable to all, but that which is knowable to those who are well trained in their intelligence; just as the absolutely wholesome is that which is wholesome to those who are well constituted in their bodiesâ€� (ἴσως δὲ καὶ τὸ ἁπλῶς γνώριμον οὐ τὸ πᾶσι γνώριμόν ἐστιν, ἀλλὰ τὸ τοῖς εὖ διακειμένοις τὴν διάνοιαν, καθάπερ καὶ τὸ ἁπλῶς ὑγιεινὸν τὸ τοῖς εὖ ἔχουσι τὸ σῶμα — p. 142, a. 9).
Hamilton’s translation misses the point of Aristotle, who here repeats what he frequently also declares in other parts of his writings (see Analyt. Post. I. i. p. 71, b. 33), namely, the contrast and antithesis between notius simpliciter (or naturâ) and notius nobis. This is a technical distinction of his own, which he had explained very fully in the page preceding the words translated by Hamilton; and the words are intended as a supplementary caution, to guard against a possible misunderstanding of the phrase. Hamilton’s words — “saying simply, and without qualification, that this or that is a known truth,â€� do not convey Aristotle’s meaning at all; again, the words — “such as are of a sound understanding,â€� fail equally in rendering what Aristotle means by τοῖς εὖ διακειμένοις τὴν διάνοιαν. Aristotle tells us distinctly (in the preceding part of the paragraph) that he intends to contrast the few minds scientific or prepared for scientific discipline, with the many minds unscientific or unprepared for such discipline: he does not intend to contrast “men of sound understandingâ€� with men “not of sound understanding.â€�
It appears to me that Hamilton has here taken a passage away from its genuine sense in the Aristotelian context, and has pressed it into his service to illustrate a view of his own, foreign to that of Aristotle. He has done the like with some other passages, to which I will now advert.
What he says, pp. 764-766, about Aristotle’s use of the term ἀξίωμα is quite opposed to the words of Aristotle himself, who plainly certifies it as being already in his time a technical term with mathematicians (Met. Γ. p. 1005, a. 20). On p. 766, a., Hamilton says that the word ἀξίωμα is not used in any work extant prior to Aristotle in a logical sense. This is true as to any work remaining to us, but Aristotle himself talks of previous philosophers or reasoners who had so used it; thus he speaks of κατὰ τὸ Ζήνωνος ἀξίωμα (Metaph. B. p. 1001, b. 7) — “according to the assumption laid down by Zeno as authoritative.â€� Of this passage Hamilton takes no notice: he only refers to the Topica, intimating a doubt (in my judgment groundless and certainly professed by few modern critics, if any) whether the Topica is a genuine work of Aristotle. In the time of Aristotle, various mathematical teachers laid down Axioms, such as, If equals be taken from equals, the remainders will be equal; In all propositions, either the affirmative or the negative must be true, &c. But the case of Zeno shows us that other philosophers also laid down Axioms of their own, which were not universally accepted by others. What Hamilton here says, about Axioms, has little pertinence as a contribution to the Philosophy of Common Sense.
Again, Hamilton says, p. 770, a.: “The native contributions by the mind itself to our concrete cognitions have, prior to their elicitation into consciousness through experience, only a potential, and in actual experience only an applied, engaged, or implicate, existence.�
These words narrow the line of distinction between the two opposite schools so much, that I cannot see where it is drawn. Every germ has in it the potentialities of that which it will afterwards become. No one disputes that a baby just born has mental potentialities not possessed by a puppy, a calf, or an acorn. What is the difference between cognitions elicited through experience, and cognitions derived from experience? To those who hold the doctrine of Relativity, both our impressions of sense and our mental activities (such as memory, discrimination, comparison, abstraction, &c.) are alike indispensable to experience. The difference, so far as I can see, between Hamilton and the Inductive School, is not so much about the process whereby cognitions are acquired, as about the mode of testing and measuring the authority of those cognitions when acquired. Hamilton will not deny that many of the cognitions which he describes as elicited by experience are untrue or exaggerated. How are we to discriminate these from the true? The Inductive School would reply: “By the test of experience, and by that alone: if these cognitions, which have been elicited in your mind through experience, are refuted or not confirmed when tested by subsequent experience carefully watched and selected for the purpose, they are not true or trustworthy cognitions.� But Hamilton would not concur in this answer: he would say that the cognitions, though elicited through experience, did not derive their authority or trustworthiness from experience, but were binding and authoritative in themselves, whether confirmed by experience or not. In speaking about Axioms, p. 764, b., he says: “Aristotle limited� (this is not correct: Aristotle did not limit as here affirmed) “the expression Axiom to those judgments which, on occasion of experience, arise naturally and necessarily in the conscious mind, and which are therefore virtually prior to experience.� That they are not prior to experience in order of time, is admitted in the words just cited from Hamilton himself: he means, therefore, prior in logical authority — carrying with them the quality of necessity, even though experience may afford no confirmation of them. This is what he says, on pp. 753-754, about causality: metaphysical causality must be believed, as a necessary and subjective law of the observer — though there is no warrant for it in experience.
The question between Hamilton and the Inductive School, I repeat, is not so much about the psychological genesis of beliefs, as about the test for distinguishing true from false or uncertified beliefs, among those beliefs which arise, often and usually, in the minds of most men. Is there any valid test other than experience itself, as intentionally varied by experiments and interpreted by careful Induction? Are we ever warranted in affirming what transcends experience, except to the extent to which the inference from Induction (from some to all) always transcends actual observation? This seems to me the real question at issue between the contending schools of Metaphysics. Hamilton, while he rejects experience as the test, furnishes no other test whereby we can discriminate the erroneous beliefs “which are elicited into consciousness through experience,� from the true beliefs which are elicited in like manner.
In discussing the doctrine which Hamilton and other philosophers entitle Common Sense (in the metaphysical import which they assign to it), it is proper to say a few words on the legitimate meaning of this phrase, before it was pressed into service by a particular school of metaphysicians. Every one who lives through childhood and boyhood up to man’s estate will unavoidably acquire a certain amount of knowledge and certain habits of believing, feeling, judging, &c.; differing materially in different ages and countries, and varying to a less degree in different individuals of the same age and country, yet still including more or less which is common to the large majority. That fire burns; that water quenches thirst and drowns; that the sun gives light and heat; that animals are all mortal and cannot live long without nourishment, — these and many other beliefs are not possessed by a very young child, but are acquired by every man as he grows up, though he cannot remember how or when he learnt them. The sum total of the beliefs thus acquired, by the impressions and influences under which every growing mind might pass, constitutes the Common Sense of a particular age and country. A person wanting in any of them would be considered, by the majority of the inhabitants, as deficient in Common Sense. If I meet an adult stranger, I presume as a matter of course that he has acquired them, and I talk to him accordingly. I also presume (being in England) that he has learnt the language of the country; and that he is familiar with the forms of English speech whereby such beliefs and their correlative disbeliefs are enunciated. If I affirm to him any one of these beliefs, he assents to it at once: it appears to him self-evident — that is, requiring no farther or extraneous evidence to support it. Though it appears to him self-evident, however, the proposition may possibly be false. To a Greek of the Aristotelian age, no proposition could appear more self-evident than that of the earth being at rest. No term can be more thoroughly relative than the term self-evident: that which appears so to one man, will often not appear so to another, and may sometimes appear altogether untrue.
But, if we suppose an individual to whom one of these beliefs does not appear self-evident, and who requires proof, he will not be satisfied to be told that every one else believes it, and that it is a dictate of Common Sense. He probably knows that already, and yet, nevertheless, he is not convinced. Aristarchus of Samos was told doubtless, often enough, that the doctrine of the earth being at rest was the plain verdict of Common Sense; but he did not the less controvert it. You must produce the independent proof which the recusant demands; and, if your doctrine is true and trustworthy, such proof can be produced. I will here remark that, in so far as Common Sense can properly be quoted as an authority or presumptive authority, it is such only in the sense proclaimed by Herakleitus and La Mennais, as cited by Hamilton, pp. 770-771: “as a magazine of ready-fabricated dogmas.� Hamilton finds fault with both of them; but it appears to me that they rightly interpret, and that he wrongly interprets, what Common Sense, as generally understood, is; and moreover, that most of the other authorities whom he himself quotes understand the phrase as these two understand it. Common Sense is “a magazine of ready-fabricated dogmas,� as La Mennais (see p. 771, a.) considers it — dogmas assumed as self-evident, and as requiring no proof. It only becomes “a source of elementary truths� when analysed and remodelled by philosophers. Now philosophers differ much in their mode of analysing it (as Hamilton himself declares emphatically), and bring out of it different elementary truths; each of them professing to follow Common Sense and quoting Common Sense as warranty. It is plain that Common Sense is no authority for either one of two discrepant modes of analysis. Its authority counts for those dogmas out of which the analysis is made, in so far as Common Sense is authoritative at all.