When we try to classify the chief of these affections of the soul according to the impulses that arouse them, we find that they may be conveniently divided into four classes:--(1.) Those caused by the liberation of impulses stored up in the soul. (2.) Those caused by impulses from other souls. (3.) Those caused by impulses from the world, as distinct from souls. (4.) Those caused by an intuition of union with the world. (1.) Here we are, above all, concerned with art. It is not necessary here to distinguish between the emotion of the artist and that of him who merely follows the artist, passing his hand as it were over the other’s work, and receiving, in a less degree it may be, the same emotion. We are all artists potentially. The secret of the charm of art is that it presents to us an external world which is manifestly of like nature with the soul. “Non merita nome di Creatore,” according to Tasso’s saying, “se non Iddio ed il Poeta.” The work of art--poem, statue, music--succeeds in being what every philosophy attempts to be. Neither change nor death can touch it; also it is immeasurable; we feel that we are in the presence of the infinite. No art has ever succeeded in embodying those visions of the infinite which are commonly regarded as specifically religious--so that even to-day we respond with a thrill of dilatation--as the old fragmentary art of Egypt in the ruined temples of the Thebaid. Greek art, also, is a manifestation of the infinite; we may lose ourselves among those subtle curves of man’s or woman’s body. A Gothic cathedral of the thirteenth century is an embodiment of the infinite world itself. The soul responds expansively to all these things. When that response is wanting, and the art therefore, however interesting, is not religious--as in the art of Pompeii and the Italian post-Raphaelite art--it will generally be found technically inferior. The subject, one may note, has little or nothing to do with the matter. A representation of God the Father rarely evokes any religious response. De Hooge, by means of mere sunlight and the rubbish of a back-yard, awakes in us an enlarging thrill of joy. In music the most indefinite and profound mysteries of the soul are revealed and placed outside us as a gracious and marvellous orb; the very secret of the soul is brought forth and set in the audible world. That is why no other art smites us with so powerfully religious an appeal as music; no other art tells us such old forgotten secrets about ourselves. “O! what is this that knows the road I came?” It is in the mightiest of all instincts, the primitive sexual traditions of the races before man was, that music is rooted.