Page images
PDF
EPUB

Before dismissing this subject, I must once more repeat, that the doctrine which I have been attempting to establish, so far from degrading axioms from that rank which Dr. Reid would assign them, tends to identify them still more than he has done with the exercise of our reasoning powers; in as much as, instead of comparing them with the data, on the accuracy of which that of our conclusion necessarily depends, it considers them as the vincula which give coherence to all the particular links of the chain; or, (to vary the metaphor) as component elements, without which the faculty of reasoning is inconceivable and impossible.*

• D'Alembert has defined the word principle exactly in the sense in which I have used it; and has expressed himself (at least on one occasion) nearly as I have done, on the subject of axioms. He seems however on this, as well as on some other logical and metaphysical questions, to have varied a little in his views (probably from mere forgetfulness) in different parts of his writings.

"What then are the truths which are entitled to have a place in the elements of philosophy? They are of two kinds; those which form the head of each part of the chain, and those which are to be found at the points where different branches of the chain unite together.

"Truths of the first kind are distinguished by this-that they do not depend on any other truths, and that they possess within themselves the whole grounds of their evidence. Some of my readers will be apt to suppose, that I here mean to speak of axioms; but these are not the truths which I have at present in view. With respect to this last class of principles, I must refer to what I have elsewhere said of them; that, notwithstanding their truth, they add nothing to our information; and that the palpable evidence which accom. panies them, amounts to nothing more than to an expression of the same idea by means of two different terms. On such occasions, the mind only turns to no purpose about its own axis, without advancing forward a single step. Accordingly, axioms are so far from hold. ing the highest rank in philosophy, that they scarcely deserve the distinction of being formally enunciated."

"Or quelles sont les vérités qui doivent entrer dans des élémens de philosophie? 11 y en a de deux sortes ; celles qui forment la tête de chaque partie de la chaine, et celles qui se trouvent au point de reunion de plusieurs branches.

"Les vérités du premier genre ont pour caractère distinctif de ne dépendre d'aucune autre, et de n'avoir de preuves que dans elles-mêmes. Plusieurs lecteurs croiront que nous voulons parler des axioms, et ils se tromperout; nous les renvoyons à ce qui nous en avons dit ailleurs, que ces sortes de principes ne nous apprennent rien à force d'être vrais, et que leur evidence palpable et grossière se reduit à exprimer la meme idée par deux termes differens, l'esprit ne fait alors autre chose que tourner inutilement sur lui-même sans avancer d'un seul pas. Ainsi les axioms bien loin de tenir en philosophie le premier rang n'ont pas même besoin d'être enoncés."-Elem. de Phil pp. 24, 25.]

Although in the foregoing passage, D'Alembert, in compliance with common phraseology, has bestowed the name of principles upon axioms, it appears clearly, from a question which occurs afterwards, that he did not consider them as well entitled to this appellation. "What are then," he asks, “in each science, the true principles from which we ought to set out ?" ("Quels sont donc dans chaque science les vrais principes d'ou l'on doit partir ?") The answer he gives to this question agrees with the doctrine 1 have stated in every par ticular, excepting in this, that it represents, (and in my opinion very incorrectly) the prin ciples of geometrical science to be (not definitions or hypotheses, but) those simple and acknowledged facts, which our senses perceive with respect to the properties of extension. "The true principles from which we ought to set out in the different sciences, are simple and acknowledged facts, which do not presuppose the existence of any others, and which, of course, it is equally vain to attempt explaining or confuting; in physics, the familiar phenomena which daily experience presents to every eye; in geometry, the sensible properties of extension; in mechanics, the impenetrability of bodies, upon which their mutual actions depend; in metaphysics, the results of our sensations; in morals, the original and common affections of the buman race."—[“ Les vrais principes d'ou l'on doit partir dans chaque science, sont des faits simples et reconnus, qui n'en supposent point d'autres, et qu'on ne puisse par consequent ni expliquer ni contester; en physique, les phénomenes journaliers que l'observation découvre à tous les yeux; en géometrie les proprietés sensibles de l'elendue; en mechanique, l'impenetrabilité des corps, source de leur action

SECTION II.

Of certain Laws of Belief, inseparably connected with the exercise of Consciousness, Memory, Perception, and Reasoning.

1. Ir is by the immediate evidence of consciousness that we are assured of the present existence of our various sensations, whether pleasant or painful; of all our affections, passions, hopes, fears, desires, and volitions. It is thus too we are assured of the present existence of those thoughts which, during our waking hours, are continually passing through the mind, and of all the different effects which they produce in furnishing employment to our intellectual faculties.

According to the common doctrine of our best philosophers,* it is by the evidence of consciousness we are assured that we ourselves exist. The proposition, however, when thus stated, is not accu

we

identy?

rately true; for our own existence (as I have elsewhere observ-How do ed,)f is not a direct or immediate object of consciousness, in the get knowl strict and logical meaning of that term. We are conscious of sensation, thought, desire, volition; but we are not conscious of the exейде орам istence of mind itself; nor would it be possible for us to arrive at existence the knowledge of it (supposing us to be created in the full posses- or mental sion of all the intellectual capacities which belong to human nature,) if no impression were ever to be made on our external senses. The moment that, in consequence of such an impression, a sensation is excited, we learn two facts at once;-the existence of the sensation, and our own existence as sentient beings;-in other words, the very first exercise of consciousness necessarily implies a belief, not only of the present existence of what is felt, but of the present existence of that which feels and thinks; or, (to employ plainer language) the present existence of that being which I denote by the words I and myself. Of these facts, however, it is the former alone of which we can properly be said to be conscious, agreeably to the rigorous interpretation of the expression. A conviction of the latter, although it seems to be so inseparable from the exercise of consciousness, that it can scarcely be considered as posterior to it in the order of time, is yet (if I may be allowed to make use of a scholastic distinction) posterior to it in the order of nature; not only as it supposes consciousness to be already awakened by some sensation, or some other mental affection; but as it is evidently rather a judgment accompanying the exercise of that power, than one of its immediate intima

mutuelle; en metaphysique, le résultat de nos sensations: en morale, les affections preunières et communes à tous les hommes."-pp. 26, 27.]

In cases of this sort, where so much depends on extreme precision and nicety in the use of words, it appears to me to be proper to verify the fidelity of my transla tions by subjoining the original passages.

* See, in particular, Campbell's Philosophy of Rhetoric.

Philosophical Essays, 4to edit. p. 7.

Personal

tions concerning its appropriate class of internal phenomena. It appears to me, therefore, more correct, to call the belief of our own existence a concomitant or accessory of the exercise of consciousness, than to say, that our existence is a fact falling under the immediate cognisance of consciousness, like the existence of the various agreeable or painful sensations which external objects excite in our minds.

2. That we cannot, without a very blameable latitude in the use of words, be said to be conscious of our personal identity, is a proposition still more indisputable; in as much as the very idea of personal identity involves the idea of time, and consequently presup identity poses the exercise not only of conciousness, but of memory. The belief connected with this idea is implied in every thought and presupposes every action of the mind, and may be justly regarded as one of the memory simplest and most essential elements of the understanding. Indeed it is impossible to conceive either an intellectual or an active being consuous to exist without it. It is, however, extremely worthy of remark,

Cogito

ergo

sum

with respect to this belief, that, universal as it is among our species, nobody but a metaphysican ever thinks of expressing it in words, or of reducing into the shape of a proposition, the truth to which it relates. To the rest of mankind, it forms not an object of knowledge; but a condition or supposition, necessarily and unconsciously involved in the exercise of all their faculties. On a part of our constitution, which is obviously one of the last or primordial elements at which it is possible to arrive in analyzing our intellectual operations, it is plainly unphilosophical to suppose, that any new light can be thrown by metaphysical discussion. All that can be done with propriety, in such cases, is to state the fact.

And here, I cannot help taking notice of the absurd and inconsistent attempts which some ingenious men have made, to explain the Descartes gradual process by which they suppose the mind to be led to the knowledge of its own existence, and of that continued identity which our constitution leads us to ascribe to it. How (it has been asked) does a child come to form the very abstract and metaphysical idea expressed by the pronoun I or moi? In answer to this question, I have only to observe, that when we set about the explanation of a phenomenon, we must proceed on the supposition that it is possible to resolve it into some more general law or laws with which we are already acquainted. But, in the case before us, how can this be expected by those, who consider that all our knowledge of mind is derived from the exercise of reflection; and that every act of this power implies a conviction of our own existence as reflecting and intelligent beings? Every theory, therefore, which pretends to account for this conviction, must necessarily involve that sort of paralogism which logicians call a petitio principii; in as much as it must resolve the thing to be explained into some law or laws, the evidence of which rests ultimately on the assumption in question. From this assumption, which is necessarily implied in the joint exercise of consciousness and memory, the philosophy of the human

mind, if we mean to study it analytically, must of necessity set out; and the very attempt to dig deeper for its foundation, betrays a total ignorance of the logical rules, according to which alone it can ever be prosecuted with any hopes of success.

It was, I believe, first remarked by M. Prevost of Geneva, (and the remark, obvious as it may appear, reflects much honour on his acuteness and sagacity) that the inquiries concerning the mind, founded on the hypothesis of the animated statue-inquiries which both Bonnet and Condillac professed to carry on analytically,—were in truth altogether synthetical. To this criticism it may be added, that their inquiries, in so far as they had for their object to explain the origin of our belief of our own existence, and of our personal identity, assumed, as the principles of their synthesis, facts at once less certain and less familiar than the problem which they were employed to resolve.

every

one

Nor is it to the metaphysician only, that the ideas of identity and Identity, & of personality are familiar. Where is the individual who has not personality experienced their powerful influence over his imagination, while he was employed in reflecting on the train of events which have filled familiar to up the past history of his life; and on that internal world, the phenomena of which have been exposed to his own inspection alone? On such an occasion, even the wonders of external nature seem com paratively insignificant; and one is tempted (with a celebrated French writer) in contemplating the spectacle of the universe, to adopt the words of the Doge of Genoa when he visited Versailles"Ce qui m'etonne le plus ici, c'est de m'y voir."*

2- Primary

perception

3. The belief which all men entertain of the existence of the material world, (I mean their belief of its existence independently of truths con that of percipient beings,) and their expectation of the continued uniformity of the laws of nature, belong to the same class of ultimate nected with or elemental laws of thought with those which have been just mentioned. The truths which form their objects are of an order so radically different from what are commonly called truths, in the popular acception of that word, that it might perhaps be useful for logicians to distinguish them by some appropriate appellation, such, for example, as that of metaphysical or transcendental truths. They are not principles or data (as will afterwards appear) from which any consequence can be deduced; but form a part of those original stamina of human reason, which are equally essential to all the pursuits of science, and to all the active concerns of life.

Primany

4. I shall only take notice farther, under this head, of the confi-r dence which we must necessarily repose in the evidence of memory truth, com(and, I may add, in the continuance of our personal indentity) when' nected with we are employed in carrying on any process of deduction or argumentation;—in following out, for instance, the steps of a long mathe; memory matical demonstration. In yielding our assent to the conclusion to which such a demonstration leads, we evidently trust to the fidelity

[What most surprises me in this place, is to see myself here.] D'Alembert, Apologie de l'Etude.

ни

Confidence in y fidelity with wh. memory con nexts things in th mind

truth.

[ocr errors]

with which our memory has connected the different links of the chain together. The reference which is often made, in the course of a demonstration, to propositions formerly proved, places the same remark in a light still stronger; and shews plainly that, in this branch of knowledge, which is justly considered as the most certain of any, the authority of the same laws of belief which are recognised in the ordinary pursuits of life, is tacitly acknowledged. Deny the evidence of memory as a ground of certain knowledge, and you destroy the foundations of mathematical science as completely as if you were to deny the truth of the axioms assumed by Euclid.

The foregoing examples sufficiently illustrate the nature of that class of truths which I have called Fundamental Laws of Human Belief, or Primary Elements of Human Reason. A variety of others, not less important, might be added to the list ;* but these I shall not at present stop to enumerate, as my chief object, in introducing the subject here, was to explain the common relation in which they all stand to deductive evidence. In this point of view, two analogies, or rather coincidences, between the truths which we have been last considering, and the mathematical axioms which were treated of formerly, immediately present themselves to our notice.

1. From neither of these classes of truths can any direct inference Analogy be drawn for the farther enlargement of our knowledge. This remark has been already shown to hold universally with respect to between the axioms of geometry; and it applies equally to what I have callthere utti. ed Fundamental Laws of Human Belief. From such propositions as these,—I exist; I am the same person to-day that I was yesterday; the mate truths material world has an existence independent of my mind; the general & math: laws of nature will continue, in future, to operate uniformly as in time past, no inference can be deduced, any more than from the intuitive truths prefixed to the Elements of Euclid. Abstracted from other data, they are perfectly barren in themselves; nor can any possible combination of them help the mind forward, one single step, in its progress. It is for this reason, that instead of calling them, with some other writers, first principles, I have distinguished them by the title of fundamental laws of belief; the former word seeming to me to denote, according to common usage, some fact, or some supposition, from which a series of consequences may be deduced.

Axioms

If the account now given of these laws of belief be just, the great argument which has been commonly urged in support of their authority, and which manifestly confounds them with what are properly called principles of reasoning, is not at all applicable to the subject;

Such, for example, as our belief of the existence of efficient causes; our belief of the existence of other intelligent beings besides ourselves, &c. &c.

Aristotle himself has more than once made this remark; more particularly, in discussing the absurd question, Whether it be possible for the same thing to be and not to be? αξιουσι δε και τουτο αποδεικνύναι τινες δι' απαιδευσίαν. εστι γαρ απαιδευσία, το μη γινωσκειν τίνων δε ζητειν αποδειξιν και τίνων ου δει. όλως μεν γαρ ἁπάντων αδύνατον αποδείξιν είναι. εις άπειρον γαρ τη βαδίζοι· ωστε μηδ' όντως είναι αποδειξιν.—Aristot. Metaphys. Vol. II. p. 873. Edit. Du Val.

« PreviousContinue »