Passing days gradually cover over those which went before and are themselves buried by those that come after.

Raising a corner of the heavy veil of habit (habit which stultifies us and which during the whole course of our existence hides more or less the whole universe from us, and under cover of utter darkness, without changing their labels, substitutes for the most dangerous or intoxicating poisons of life something anodyne which procures no delight), these memories returned to me as on their first appearance, with the same sharp, fresh novelty that each new season brings as it returns, changing our routine time-table and providing us, even in the realm of our pleasures - if we climb into a carriage on the first fine day of spring or leave the house at sunrise - with an exultant awareness of our most insignificant actions, which invests this one intense moment with more value than the totality of the days preceding it. As they recede, passing days gradually cover over those which went before and are themselves buried by those that come after. But each past day remains deposited within us as in some vast library where there are copies even of the oldest books, which probably no one will ever ask to consult. And yet if this past day should pass through the translucent layers of the folowing eras, rise to the surface and spread out from within us until it covers our whole surface, then for a moment names will resume their former meanings, people their former faces and we our former souls, and we shall feel with a diffuse but newly tolerable and transient sense of suffering, the problems which remained intractable for so long and which caused us so much anguish at the time. Our selves are composed of successive states, superimposed. But this superimposition is not immutable like the stratification of a mountain. A tremor is liable at any moment to throw older layers back up to the surface.

quoted in:
Proust, Marcel
"The Fugitive" (In Search Of Lost Time, Volume 5)
p. 509, Penguin Classics, 2003