I venture to repeat in conclusion that there is nothing dogmatic about these ideas. They are subject to criticism and objection, for we are groping in the dark towards what Mr Leonard Inkster calls the standardisation of artistic terms; if I prefer to his scientific way the more inspired suggestion of 'esperanto,' that is a common language of the arts, it is without fear of being called metaphysical. It may be argued that a purely intellectual attempt to extract and correlate the inspirations of forms of art is a metaphysical exercise doomed to failure by its own ambition. I do not think so. For art is universal enough to contain all the appeals, the sensuous, the intellectual, and, for those who perceive it, the spiritual; but the sensuous is incapable of explanation because sensuousness is a thing of perceptions which vanish as soon as the brain attempts to state them in mental terms; and the spiritual, which I will define much as I would faith as a stimulation produced by a thing which one knows to be inexistent, also resists analysis; if we are to bridge the gulfs that separate the various forms of art, some intellectual process must be applied. Now it may be metaphysical to treat of the soul in terms of the intellect, but the intellect has never in philosophic matters refrained from laying hands upon the alleged soul of man; I see no reason, therefore, to place art higher than the essence of human life and grant it immunity from attack and exegesis by the intellect. Indeed, the intellect in its metaphysical moods is alone capable of solving the riddle of artistic sensation. Once defined by intellect and applied by intellect, the esperanto of the arts may well serve to reconcile them and demonstrate to their various forms, against their will, their fundamental unity. The Twilight of Genius I