The only form of metaphor which may be used by the painter is that wherein a beautiful symbol typifies a high abstract quality. Metaphor belongs properly to the arts of the poet and novelist who can indicate the symbol and things symbolized in immediate succession, so that the whole meaning is apparent. The painter can only represent the symbol, and unless this is beautiful and its purport readily comprehended, his sign is merely a hieroglyph--a sign of writing. Secondary art includes symbolic painting when the symbol may represent either the symbol itself or the thing symbolized, for such a condition involves a confusion of ideas which tends to destroy the æsthetic effect of the work. The most notable painting of this kind is Holman Hunt's The Scapegoat, where the design shows only a goat in desert country. The scapegoat has ceased to be an actuality for centuries, and the only meaning of the term as it is now used applies to a man: hence, with the title the goat appears to be a symbol of both a man and an animal, while without the title it is merely the image of a goat without symbolism. But the conception of an animal of any kind as a symbol is foreign to the art of the painter whose symbol should always be beautiful, whatever the nature of the representation. CHAPTER XV COLOUR In itself colour has no virtues which are not governed by immutable laws. These are apart from the exercise of human faculties, the recognition of colour harmony being involuntary and entirely dependent upon the condition of the optic nerves. Thus there can be no meaning in colour apart from its application to form, and the extent to which it may be properly used in the representation of form is necessarily bound by our experience of nature. Other things being equal, the most perfect painting is that wherein there is a just balance between the colour and the form, that is to say, where the colour is not so vivid as to act upon the sense nerves before the general beauty of the work is appreciated, or so feeble or discordant that its want of natural truth is immediately presented to the mind, thus disturbing the impression of the design.