Form, we have seen, is, through our selection among the possible signs present, within certain limits what we like to make it. As it varies, so do our further or deeper responses of feeling and attitude vary. But just as there are congruences and compatibilities among the responses we make, in the case of colour, which tend, given certain colours, to make us pick out of a range of possible colours one which will give us a congruent (or harmonious) response, so it is with form. Out of the multitude of different forms which we might construct by stressing certain of the signs rather than others, the fixing even temporarily of a part of the form tends to bias us towards so interpreting the rest as to yield responses accordant with those already active. Hence a great reduction of the disparity of the interpretations which arise, hence also the danger of an initial misapprehension which perverts the rest of the interpretation. This Chapter, like the last, is intended as an indication, merely, of the ways in which a psychological analysis may assist the critic and help to remove misconceptions. The usual practice of alluding to Form as though it were a simple unanalysable virtue of objects—a procedure most discouraging to those who like to know what they are doing, and thus very detrimental to general appreciation—will lapse when a better understanding of the situation becomes general. None the less there are certain very puzzling facts as to the effects of forms when apprehended which in part explain this way of talking. These are perhaps best considered in connection with Music, the most purely formal of the arts. [54] This remark applies equally strongly to the attempts which are from time to time made to find formulæ for the proportions of buildings. No one with an adequate idea of the complexity of the factors which determine our responses is likely to attach great importance to these investigations, interesting though they are. The interpretation of the results is not within sight of even the most optimistic of psychologists. CHAPTER XX The _Impasse_ of Musical Theory Will twenty chapters render plain Those lonely lights that still remain Just breaking over land and main?