In a whole of differentiated members, such as a square, all this begins to be different. A side in a square possesses, by the fact of being a side, very different relations and properties from those of a straight line conceived in isolation. In this case the whole is not made up merely by adding the parts together. It is a geometrical whole, and its parts are combined according to a special form of necessity which is rooted in the nature of space. Speaking generally, the point is that parts must occupy certain perfectly definite places as regards each other. You cannot make a square by merely adding three right angles to one, nor by taking a given straight line and adding three more equal straight lines to its length. You must construct in a definite way so as to fulfil definite conditions. The identity shows itself in the different elements which make it up, not as a mere repeated quality, but as a property of contributing, each part in a distinctive way, to the nature of the whole. Such an identity is not a mere total or sum, though I imagine that its relations can be fully expressed in terms of quantity, certain differentiated objects or conceptions being given (e.g. line and angle).
I take a further instance to put a sharp point upon this distinction. The relation of whole and parts is nowhere more perfect, short of a living mind, than in a work of art. There is a very fine Turner landscape now [1] in the “Old {56} Masters” Exhibition at Burlington House—the picture of the two bridges at Walton-on-Thames. The picture is full of detail—figures, animals, trees, and a curving river-bed. But I am told that if one attempts to cut out the smallest appreciable fragment of all this detail, one will find that it cannot be done without ruining the whole effect of the picture. That means that the individual totality is so welded together by the master’s selective composition, that, according to Aristotle’s definition of a true “whole,” if any part is modified or removed the total is entirely altered, “for that of which the presence or absence makes no difference is no true part of the whole.” [2]
[1] February 1892. [2] Poetics, 8
Of course, in saying that the part is thus essential to the whole, it is implied that the whole reacts upon and transfigures the part. It is in and by this transformation that its pervading identity makes itself felt throughout all the elements by which it is constituted. As the picture would be ruined if a little patch of colour were removed, so the little patch of colour might be such as to be devoid of all value if seen on a piece of paper by itself. I will give an extreme instance, almost amounting to a tour de force, from the art of poetry, in illustration of this principle. We constantly hear and use in daily life the phrase, “It all comes to the same thing in the end.” Perhaps in the very commonest speech we use it less fully, omitting the word “thing”; but the sentence as written above is a perfectly familiar platitude, with no special import, nor grace of sound or rhythm. Now, in one of the closing stanzas of Browning’s poem Any Wife to Any Husband, this sentence, only modified {57} by the substitution of “at” for “in,” forms an entire line. [1] And I think it will generally be felt that there are few more stately and pathetic passages than this in modern poetry. Both the rhythm and sonorousness of the whole poem, and also its burden of ideal feeling, are communicated to the line in question by the context in which it is framed. Through the rhythm thus prescribed to it, and through the characteristic emotion which it contributes to reveal, the “whole” of the poem re-acts upon this part, and confers upon it a quality which, apart from such a setting, we should never have dreamed that it was capable of possessing.
[1] In order to remind the reader of the effect of this passage it is necessary to quote a few lines before and after—
“Re-issue words and looks from the old mint,
Pass them afresh, no matter whose the print,
Image and superscription once they bore!
Re-coin thyself and give it them to spend,—
It all comes to the same thing at the end,
Since mine thou wast, mine art and mine shalt be,
Faithful or faithless, sealing up the sum
Or lavish of my treasure, thou must come
Back to the heart’s place here I keep for thee!”
We are not here concerned with the peculiar “aesthetic” nature of works of art, which makes them, although rational, nevertheless unique individuals. I only adduced the above examples to show, in unmistakable cases, what is actually meant when we speak of “a whole” as constituted by a pervading identity which exhibits itself in the congruous or co-operating nature of all the constituent parts. In wholes of a higher kind than the whole of mere quantity the parts no longer repeat each other. They are not merely distinct, {58} but different. Yet the common or continuous nature shows itself within each of them.
The parts of a sum-total, taking them for convenience of summation as equal parts, may be called units; [1] the parts of an abstract system, such as a geometrical figure, may be called elements (I cannot answer for mathematical usage), and the parts of a concrete system, an aesthetic product, a mind, or a society, might be called members.
[1] A unit of measurement implies in addition that it has been equated with some accepted standard. If I divide the length of my room into thirty equal parts, each part is a “unit” in the sum-total; but I have not measured the room till I have equated one such part with a known standard, and thus made it into a unit in the general system of length equations.
But every kind of whole is an identity, and its parts are always differences within it.