And this pleasure, different from every other, had in the end created in him a need of her, which she alone, by her presence or by her letters, could assuage, almost as disinterested, almost as artistic, as perverse as another need which characterised this new period in Swann's life, when the sereness, the depression of the preceding years had been followed by a sort of spiritual superabundance, without his knowing to what he owed this unlooked-for enrichment of his life, any more than a person in delicate health who from a certain moment grows stronger, puts on flesh, and seems for a time to be on the road to a complete recovery:—this other need, which, too, developed in him independently of the visible, material world, was the need to listen to music and to learn to know it.