Also at this point a query arises, irrelevant indeed, but hardly to be suppressed:  “Why are we so profoundly moved by forms related in a particular way?” The question is extremely interesting, but irrelevant to aesthetics.  In pure aesthetics we have only to consider our emotion and its object:  for the purposes of aesthetics we have no right, neither is there any necessity, to pry behind the object into the state of mind of him who made it.  Later, I shall attempt to answer the question; for by so doing I may be able to develop my theory of the relation of art to life.  I shall not, however, be under the delusion that I am rounding off my theory of aesthetics.  For a discussion of aesthetics, it need be agreed only that forms arranged and combined according to certain unknown and mysterious laws do move us in a particular way, and that it is the business of an artist so to combine and arrange them that they shall move us.  These moving combinations and arrangements I have called, for the sake of convenience and for a reason that will appear later, “Significant Form.”

A third interruption has to be met.  “Are you forgetting about colour?” someone inquires.  Certainly not; my term “significant form” included combinations of lines and of colours.  The distinction between form and colour is an unreal one; you cannot conceive a colourless line or a colourless space; neither can you conceive a formless relation of colours.  In a black and white drawing the spaces are all white and all are bounded by black lines; in most oil paintings the spaces are multi-coloured and so are the boundaries; you cannot imagine a boundary line without any content, or a content without a boundary line.  Therefore, when I speak of significant form, I mean a combination of lines and colours (counting white and black as colours) that moves me aesthetically.

Some people may be surprised at my not having called this “beauty.”  Of course, to those who define beauty as “combinations of lines and colours that provoke aesthetic emotion,” I willingly concede the right of substituting their word for mine.  But most of us, however strict we may be, are apt to apply the epithet “beautiful” to objects that do not provoke that peculiar emotion produced by works of art.  Everyone, I suspect, has called a butterfly or a flower beautiful.  Does anyone feel the same kind of emotion for a butterfly or a flower that he feels for a cathedral or a picture?  Surely, it is not what I call an aesthetic emotion that most of us feel, generally, for natural beauty.  I shall suggest, later, that some people may, occasionally, see in nature what we see in art, and feel for her an aesthetic emotion; but I am satisfied that, as a rule, most people feel a very different kind of emotion for birds and flowers and the wings of butterflies from that which they feel for pictures, pots, temples and statues.  Why these beautiful things do not move us as works of art move is another, and not an aesthetic, question.  For our immediate purpose we have to discover only what quality is common to objects that do move us as works of art.  In the last part of this chapter, when I try to answer the question—­“Why are we so profoundly moved by some combinations of lines and colours?” I shall hope to offer an acceptable explanation of why we are less profoundly moved by others.