animals. The reason alluded to-which is the only one given by Berkeley-is, I grant, and as I have shown in another place, exceedingly weak, unmeaning, and confused, and has really no applicability to the matter which it is intended to prove: but such as it is, if it is good against the human organ of vision, it is good against all organs of vision whatever. The parity of the two cases has, indeed, been slighted or hurried over by the defenders of the good bishop, but any one who takes the trouble to scrutinize the argument, will see the asserted parity at once and that it is fatal to the theory.

Adam Smith without discerning this inevitable conclusion, made the same admission with regard to sight in the lower animals that Sir Wm. Hamilton confesses himself to have conceded with so much unphilosophical reluctance. Who in truth at all acquainted with such facts as the following can possibly avoid it?

"Sight," says Cuvier, "is extremely perfect in birds, and they have the peculiar faculty of seeing objects near and distant equally well. The means by which this is effected are not satisfactorily explained, though a power of changing the convexity of the eye is probably the proximate cause. Like all other physical peculiarities, it is admirably adapted to the mode of existence of the class; a

Review of Berkeley's Theory of Vision; also Theory of Reasoning, Appendix.

quick and perfect sight of objects and perception of distances is necessary to the rapidity of movements and the securing of their prey to birds."*

It is afterwards said of eagles in the same work, that their admirable power of vision enables them "to distinguish their prey at an immense distance, and they rush upon it with the velocity of an arrow." †

Just indulge your imagination for a moment in the exquisite supposition that the eagle learns distances by the touch!

If I have appeared to bestow too much time and labour in setting forth these erroneous views (as I conceive them to be) I must allege the high authority of the author on whom I am commenting in justification of the pains I have taken in pointing them out. Any confusion and inconsistency in a writer of his reputation must tend to produce a painful kind of perplexity in the mind of the earnest student. A philosopher of mature reflection may be able to detect such incongruities, and to divine their sources, and will at all events experience little disturbance from them in his own wellconsidered views; but it is in the process of education chiefly that the work on which I have animadverted is likely to be studied; and it is the young mind eager after knowledge that has to be guarded from embarrassment.

* Cuvier's Animal Kingdom, translated by Ed. Griffith, vol. vi. p. 102.

† Page 223.

LETTER V.

GENERAL AND ABSTRACT IDEAS AND TERMS, AS TREATED BY BERKELEY, HUME, AND OTHER WRITERS OF A MORE RECENT DATE.

I PROMISED in a preceding letter to furnish some proof that the philosophers who had in recent times maintained, more decidedly perhaps than any others, the non-existence of general and abstract ideas, had not, while so doing, steered altogether clear of inconsistencies and inaccuracies, or, at any rate, infelicities of exposition.

In attempting to fulfil the promise, I give precedence to the distinguished author of "A Treatise concerning the Principles of Human Knowledge."

Berkeley, while denying general and abstract ideas as commonly understood, still teaches that a particular idea may become general by being made to represent or stand for all other particular ideas of the same sort, just in the same way as a proper name may become general.*

Surely there is here a want of due discrimination.

Introduction to the Principles of Human Knowledge,

sect. 12.

F

The reason he assigns for the application of the epithet "general" to an idea, namely, that it represents other ideas, would not be valid even if the description of its function as representative were correct and further, if the epithet were allowed to be appropriate, the meaning of it could not be the same, the case being a totally different one from the generalization of a name to which he likens it. The justness of this objection will be more clearly seen if we consider that the term "general," when applied to names, means "common," or belonging in common to the individuals of a genus or class.

A proper name may undoubtedly lose its particularity and become common or general by being given to more objects than one, and will then belong alike to each object: but a particular idea can never in any analogous sense be applied to other particular ideas or belong to them in common, and therefore cannot become general in the same sense as a name becomes so.

Moreover, if an idea can with any propriety be called general because, as alleged, it represents a class, so may an object; for an object actually perceived may represent other objects (whatever may be meant by the process so designated) just as well as an idea can represent other ideas: both stand in the same relation (however it may be described) to the other individuals of their respective classes.

It is curious enough that Berkeley himself, with apparent unconsciousness of what he is doing, asserts the same thing; for while attempting to show how an idea may become general by this kind of representation, he is actually engaged in showing how an object, and incidentally a name, may become general.

"Now," he says, "if we will annex a meaning to our words, and speak only of what we can conceive, I believe that we shall acknowledge that an idea which, considered in itself, is particular, becomes general by being made to represent or stand for all other particular ideas of the same sort. To make this plain by an example, suppose a geometrician is demonstrating the method of cutting a line in two equal parts. He draws, for instance, a black line of an inch in length; this, which in itself is a particular line, is nevertheless, with regard to its signification, general, since, as it is there used, it represents all particular lines whatsoever; so that what is demonstrated of it, is demonstrated of all lines, or, in other words, of a line in general. And as that particular line becomes general by being made a sign, so the name line, which taken absolutely is particular, by being a sign is made general. And as the former owes its generality, not to its being the sign of an abstract or general line, but of all particular right lines that may possibly exist; so the latter must be thought to derive its