The same definition of rhythm may be extended to the plastic arts and to architecture. Temporal sequence is not strictly necessary for rhythm, though in the vast majority of cases it is involved. The attention usually passes successively from one complex to another, the expectations, the readiness to perceive this rather than that, aroused by the one being either satisfied or surprised by the other. Surprise plays an equally important part here; and the difference in detail between a surprising and delightful variation and one which merely irritates and breaks down the rhythm, as we say, is here, as elsewhere, a matter of the combination and resolution of impulses too subtle for our present means of investigation. All depends upon whether what comes can be an ingredient in the further response, or whether the mind must, as it were, start anew; in more ordinary language, upon whether there is any ‘connection’ between the parts of the whole. But the rhythmic elements in a picture or a building may be not successive but simultaneous. A quick reader who sees a word as a whole commonly overlooks misprints because the general form of the word is such that he is only able at that instant to perceive one particular letter in a particular place and so overlooks what is discrepant. The parts of a visual field exert what amounts to a simultaneous influence over one another. More strictly what is discrepant does not get through to more central regions. Similarly, with those far more intricate wholes, made up of all kinds of imagery and incipient action of which works of art consist. The parts of a growing response mutually modify one another and this is all that is required for rhythm to be possible.