trine.' This view, according to which the reason or understanding is the source of certain simple ideas, such as identity, causation, equality, which ideas are necessarily involved in the intuitive judgments which we form, when we recognize fundamental truths of science, approaches very near in effect to the doctrine which in this work we have presented, of fundamental ideas belonging to each science, and manifesting themselves in the axioms of the science. It may be observed, however, that by attempting to enumerate these ideas and axioms, so as to lay the foundations of the whole body of physical science, and by endeavoring, as far as possible, to simplify and connect each group of such ideas, we have at least given a more systematic form to this doctrine. We have, moreover, traced it into many consequences to which it necessarily leads, but which do not appear to have been contemplated by the metaphysicians of the Scotch school. But I gladly acknowledge my obligations to the writers of that school; and I trust that in the near agreement of my views on such points with theirs, there is ground for believing the system of philosophy which I have in this work presented, to be that to which the minds of thoughtful men, who have meditated on such subjects, are generally tending."

-lb. pp. 471, 472.

Our author's general theory on the subject on which he treats, so far as we can gather it (for we have already intimated that we sometimes desiderate that perfect clearness in metaphysical discussions which speak the long practised writer on such subjects), is as follows. Adopting essentially the same views as Brown and other metaphysicians in discarding that perversion of the doctrine of Locke* which represents all our knowledge as derived simply from our sensations, our author contends that from the very constitution of the human mind, there are

* We have used the words 'perversion of Locke's doctrine,' because we are and have long been convinced, that he would have given no countenance whatever to the system which attributes all our knowledge to sensation alone, or rather, which (according to Condorcet) considers all knowledge as in fact sensation in some form or other. All, we are pretty certain, that Locke really intended to assert was the doctrine-now universally conceded, and that too as Dugald Stewart remarks) even by such adversaries of Locke's philosophy as Lord Monboddo and Mr. Harris,-that all our knowledge is ultimately derivable from sensation in this sense, that it furnishes, in point of fact, the necessary condition of the development of our intellectual faculties, and that without it, for anything we know, they must for ever have remained dormant. It may be said, there are expressions in Locke which seem inconsistent with this, and to imply more. We reply, with the abovementioned writer, that they ought to be interpreted by the many clearer passages in which he distinctly asserts that 'reflection' is another and distinct source of ideas. Many of these passages Dugald Stewart has cited in his Dissertation,' prefixed to the Encyclopædia Britannica, and many others might be added to them. The phrase that all our knowledge is derived from sensation,' is ambiguous, and may mean either that sensation is ultimately the universal condition of all our knowledge, which none now deny, or that

evolved in the exercise of its faculties certain very abstract and general modes of thought which are distinct from every thing which our sensations involve, and which mere sensation cannot impart. Such are the ideas of equality,' of 'relation,' of ' number,' of 'cause and effect,' and so on. Such as these our author calls ideas;' not very wisely, as it appears to us, since it is a term which has been already so variously and loosely employed. These 'Ideas' he does not very clearly define, while the various attempts which he has made to describe them would seem to imply that he himself has some doubts whether he has been in any quite successful. I use 'the term 'idea," he says, 'to designate those inevitable general ' relations which are imposed upon our perceptions by acts of the mind, and which are different from anything which our senses directly offer to us.' Again, I restrict its application to the relations and conditions which are imposed on our 'sensations through the activity of our mind.' Again, 'Sensations are the objective and ideas the subjective part of every act of perception or knowledge.' These comprehensive general notions, our author calls Fundamental Ideas.' That we have such comprehensive notions as, for example, of resemblance, of number, of figure, of cause and effect, &c., we are of course far enough from denying, but we confess we should have been much gratified by a somewhat clearer account of them, and feel the need of a more exact criterion for discriminating and classifying those which are really such. Moreover, whether it be practicable successfully to prosecute such an investigation or not, we should have liked at least a little more discussion as to the possibility of tracing their historic origin-the mode in which they may be conceived to be evolved in the development of the human mind, or as to the reasons why it is vain to prosecute such inquiries; nor do we think that the philosophy of the subject can be considered complete without it. Our author's general statements show that he thinks our 'Fundamental Ideas' (in his sense of the terms) are neither derived from experience, nor to be accounted abstractions derived from particular cases. For our own parts we are not convinced of this latter assertion, although we profess not to have formed any satisfac tory theory upon the subject. But it might surely be expected that something more would be said as to the modes in which they be supposed to be originated, or the reasons why we can form

may

(though it is not so proper or natural a sense) there is no other source of our knowledge than sensation. In the former sense, even Monboddo uses it. Dr. Hartley, one of the champions of the 'sensational school,' understood Locke aright. 'It appears to me,' he says, 'that all the most complex ideas arise from sensation, and that reflection is not a distinct source, as Mr. Locke makes it.'

no supposition on the subject. The mind once possessed them not; it is now found possessed of them. How came it by them? Does our author believe them to be 'innate,' in the sense in which Locke exploded the doctrine of innate ideas? We suppose not. Professor Whewell freely admits that both ideas and sensations are essential to our knowledge: will he also admit that sensation to some extent or other is also an essential precondition of the actual development of these ideas? We doubt whether he would deny t; and if so, though it is most true, as he contends, that these ideas are characterized by properties which do not belong to our sensations, and that the propositions of which they are the terms (as for example that every effect must have a cause') have a universality and necessity which cannot be imparted by experience alone, the statement that they are not derived from sensation or experience is in a certain sense ambiguous, and requires to be guarded against.

We cannot help being of opinion, upon the whole, that our author has not adequately treated the metaphysics of this difficult subject; for we suppose that no one will accept the following statement of the Idea of Space,' for example, and which deserves to be called an instance of illustrating obscurum per obscurius, as a sufficiently clear and distinct exposition of the 'philosophy' of the subject. We have an Intuition of objects in space; that is, we contemplate objects as made up of spatial parts, and apprehend their spatial relations by the same act by 'which we apprehend the objects themselves.'

But to proceed with Professor Whewell's general views.Having supplied us with certain 'Fundamental Ideas,' though in our opinion he has been far from clearly explaining his views of their nature, origin, and historic development, he proceeds to designate as Ideal Conceptions' certain less general forms of the Fundamental Ideas;' thus 'a circle,' a square,' is an ideal conception appertaining to the 'Funda'mental Idea of Space;' a square number,' a cube number,' to that of number; 'a central force' to that of 'cause;' and so on. This, the reader will perceive, is a limitation of the term 'conception,' as arbitrary and as little sanctioned by previous usage, as that of Idea.' This, however, is of little consequence provided the meaning attached to the term be clearly explained and duly remembered. A more serious objection is, that it is by no means always easy to discriminate the said 'Ideal Conceptions' from the 'Fundamental Ideas,' an admission which our author himself makes. Since,' says he, the Ideal Con'ceptions, of which we here speak, are only modifications and 'limitations of the Fundamental Ideas themselves, the reader

' will not think it strange that sometimes it may not be easy to 'draw a line of distinction between Ideas and Conceptions, in 'the senses in which we have used the terms. The modification may be of so comprehensive a character, that it may appear almost as extensive as the idea itself, and as well fitted to supply a foundation for general truths.'-vol. i. p. 39. It appears that these Ideal Conceptions are intended, however novel the phrase, to designate neither more nor less than the notion conveyed by 'general terms,' and we are happy to find that the views of our author on this subject are in no essential respect different from those of Dr. Thomas Brown, who has so successfully exploded the errors of both the Nominalists and Realists. The former had often been pretty thoroughly demolished before; not so the latter. We have much pleasure in recommending to the attention of the reader our author's observations in relation to this much perplexed controversy.

Our author next proceeds to illustrate the following points, previous to an examination of what are the 'Fundamental Ideas' and Ideal Conceptions' which peculiarly belong to each science. They are more fully illustrated again, however, in the second volume. He remarks that observed facts are connected in such a way as to produce new truths by superinducing upon them an Idea, and that such truths are obtained by induction; that truths thus obtained are in their turn facts-which may be again combined so as to produce more general truths, and to form in fact the stepping-stones of successive generalizations; that these truths are made compact and permanent by being expressed in technical terms; that experience cannot conduct us to universal truths, inasmuch as she has not tried all cases, nor to necessary, because necessity is not a matter on which experience can testify;-in other words, that experience can strictly tell us only what has been in particular cases-not what will be, or must be; and that such truths derive their necessity and universality only from the Ideas they involve, and that the existence of necessary truths proves the existence of Ideas not to be gener ated by experience. But here we come back to the old question, how is it that these Ideas, by which we can give universality and necessity to certain truths, are generated? And moreover, how is it that there are truths which, as Professor Whewell admits, are confessedly universal and apparently necessary, and which nevertheless, historically speaking, were established by experiment, as for example, the Laws of Motion? Our author devotes a subsequent chapter to the examination of this 'Paradox,' as he very justly calls it. We cannot say that the investigation has to our mind quite removed the cloud from it: but we give the terms of the solution, hoping that they may prove more satis

factory to our readers than they have been to us. "The solu'tion of this paradox,' he says, 'is that these laws [of motion] are interpretations of the Axioms of Causation. The axioms are universally and necessarily true, but the right interpretation of the terms which they involve is learnt by experience. 'Our Idea of Cause supplies the Form-experience the Matter ' of these laws.' But (the troublesome question again recurs) how did the Idea of Cause, and its universally and necessarily 'true axioms' originate? For our own parts, though we quite believe that the general Ideas of Cause, and of the Laws of Motion possess characteristics which mere experience cannot impart, we are by no means sure that they are not alike abstractions collected from experience, a general expression derived from particular facts-in other words, that they are not the fruit of that generalizing faculty which subjects to its operations, as in an intellectual alembic, all the individual lessons of experience. But, as we have already said, we profess not to have formed a determinate theory upon the subject; our business is not to speculate but to endeavor to give some account of the speculations of our author.

Professor Whewell devotes several books,-indeed the greater part of the first volume, and a considerable portion of the second -to an examination of what are the Fundamental Ideas and Ideal Conceptions (understood according to his preceding explication), which lie at the basis of the several sciences of 'Induction. The principal Fundamental Ideas which it is necessary to consider, according to him, are as follows:

'I shall, then, successively, have to speak of the ideas which are the foundation of geometry and arithmetic (and which also regulate all sciences depending upon these, as astronomy and mechanics); namely, the ideas of space, time, and number:

Of the ideas on which the mechanical sciences (as mechanics, hydrostatics, physical astronomy) more peculiarly rest; the ideas of force and matter, or rather the idea of cause, which is the basis of these:

'Of the ideas which the secondary mechanical sciences (acoustics, optics, and thermotics) involve; namely, the ideas of the externality of objects, and of the media by which we perceive their qualities:

"Of the ideas which are the basis of mechanico-chemical and chemical sciences, polarity, chemical affinity, and substance; and the idea of symmetry a necessary part of the philosophy of crystallography:

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Of the ideas on which the classificatory sciences proceed (mineralogy, botany, and zoology); namely, the ideas of resemblance, and of its gradations, and of natural affinity:

Finally, of those ideas on which the physiological sciences are founded; the ideas of separate vital powers, such as assimilation and irritability; and the idea of final cause.