This operation of mind, so far as I can see, is absolutely [§ 8. Material analogy with imagination.]inexplicable, but there is something like it in chemistry.
"The action of sulphuric acid on metallic zinc affords an instance of what was once called disposing affinity. Zinc decomposes pure water at common temperatures with extreme slowness; but as soon as sulphuric acid is added, decomposition of the water takes place rapidly, though the acid merely unites with oxide of zinc. The former explanation was, that the affinity of the acid for oxide of zinc disposed the metal to unite with oxygen, and thus enabled it to decompose water; that is, the oxide of zinc was supposed to produce an effect previous to its existence. The obscurity of this explanation arises from regarding changes as consecutive, which are in reality simultaneous. There is no succession in the process, the oxide of zinc is not formed previously to its combination with the acid, but at the same instant. There is, as it were, but one chemical change, which consists in the combination at one and the same moment of zinc with oxygen, and of oxide of zinc with the acid; and this change occurs because these two affinities, acting together, overcome the attraction of oxygen and hydrogen for one another."[[52]]
Now, if the imaginative artist will permit us, with all deference, to represent his combining intelligence under the figure of sulphuric acid; and if we suppose the fragment of zinc to be embarrassed among infinitely numerous fragments of diverse metals, and the oxygen dispersed and mingled among gases countless and indistinguishable, we shall have an excellent type in material things of the action of the imagination on the immaterial. Both actions are, I think, inexplicable, for however simultaneous the chemical changes may be, yet the causing power is the affinity of the acid for what has no existence. It is neither to be explained how that affinity operates on atoms uncombined, nor how the artist's desire for an unconceived whole prompts him to the selection of necessary divisions.
Now, this operation would be wonderful enough, if it were concerned with two ideas only. But a powerfully imaginative mind seizes and combines [§ 9. The grasp and dignity of imagination.]at the same instant, not only two, but all the important ideas of its poem or picture, and while it works with any one of them, it is at the same instant working with and modifying all in their relations to it, never losing sight of their bearings on each other; as the motion of a snake's body goes through all parts at once, and its volition acts at the same instant in coils that go contrary ways.
This faculty is indeed something that looks as if man were made after the image of God. It is inconceivable, admirable, altogether divine; and yet wonderful as it may seem, it is palpably evident that no less an operation is necessary for the production of any great work, for, by the definition of unity of membership, (the essential characteristic of greatness,) not only certain couples or groups of parts, but all the parts of a noble work must be separately imperfect; each must imply, and ask for all the rest, and the glory of every one of them must consist in its relation to the rest, neither while so much as one is wanting can any be right. And it is evidently impossible to conceive in each separate feature, a certain want or wrongness which can only be corrected by the other features of the picture, (not by one or two merely, but by all,) unless together with the want, we conceive also of what is wanted, that is of all the rest of the work or picture. Hence Fuseli:—
"Second thoughts are admissible in painting and poetry only as dressers of the first conception; no great idea was ever formed in fragments."
"He alone can conceive and compose who sees the whole at once before him."
There is, however, a limit to the power of all human imagination. When the relations to be observed are absolutely necessary, and highly [§ 10. Its limits.]complicated, the mind cannot grasp them, and the result is a total deprivation of all power of imagination associative in such matter. For this reason, no human mind has ever conceived a new animal. For as it is evident that in an animal, every part implies all the rest; that is, the form of the eye involves the form of the brow and nose, these the form of the forehead and lip, these of the head and chin, and so on, so that it is physically impossible to conceive of any one of these members, unless we conceive the relation it bears to the whole animal; and as this relation is necessary, certain, and complicated, allowing of no license or inaccuracy, the intellect utterly fails under the load, and is reduced to mere composition, putting the bird's wing on men's shoulders, or half the human body to half the horse's, in doing which there is no action of imagination, but only of fancy; though in the treatment and contemplation of the compound form there may be much imagination, as we shall presently see. ([Chap. III. § 30].)
The matter, therefore, in which associative imagination can be shown is [§ 11. How manifested in treatment of uncertain relations. Its deficiency illustrated.]that which admits of great license and variety of arrangements, and in which a certain amount of relation only is required; as especially in the elements of landscape painting, in which best it may be illustrated.