Art is, then, that which gives a pure emotion,--that is to say, an emotion without vibrations beyond a limited group of cells. It is that which invites to neither virtue nor patriotism, nor debauch, nor peace, nor war, nor laughter, nor tears, nor anything other than art itself. Art is impassible, and as an old Italian poet said of love, _non piange, nè ride_. There is nothing about it either rational, or just, or consistent with any truth. It is a matter of the manners and customs of an intellectual caste. Born of an imperfection in the nervous system, the idea of beauty has picked up, on the way, all sorts of rules, prejudices, beliefs, habits, and it has constructed itself a canon whose form, without being absolute, fluctuates at any given moment between certain limits only. The restriction is necessary. All refined men of an epoch agree on the idea of beauty. To-day, for example, there are certain touchstones: Verlaine, Mallarmé, Rodin, Monet, Nietzsche. To admit that you are not moved by the _Hands_, by _Hérodiade_, by _Eve_, by the _Cathédrales_, by _Zarathoustra_, is to admit that you are devoid of aesthetic sensibility. But works of quite another tone were formerly admired by the same human group. From Ronsard to Victor Hugo, the principle of beauty was sought in imitation. Artists imitated the classics, the Italians, the Spaniards, the English. In the last century, it was the effort after originality; and this produced even a few years ago an excess of false notes, but a music less flat, on the whole, than that which had so long wearied the Muses. Not that the artist imitated less, but he did so in the illusion of creating something new, and illusion is almost always productive. France is, moreover, the country where the idea of beauty has undergone the greatest number of variations, since it is peopled by an animated, eager race always attentive to what is happening and ready to make the acquaintance of everything strange and new, reserving the right to laugh at this novelty, if it does not suit their temperament.