Janet

“I call it Joy. 'Animal-Land' was not imaginative. But certain other experiences were... The first is itself the memory of a memory. As I stood beside a flowering currant bush on a summer day there suddenly arose in me without warning, and as if from a depth not of years but of centuries, the memory of that earlier morning at the Old House when my brother had brought his toy garden into the nursery. It is difficult or find words strong enough for the sensation which came over me; Milton's 'enormous bliss' of Eden (giving the full, ancient meaning to 'enormous') comes somewhere near it. It was a sensation, of course, of desire; but desire for what?...Before I knew what I desired, the desire itself was gone, the whole glimpse... withdrawn, the world turned commonplace again, or only stirred by a longing for the longing that had just ceased... In a sense the central story of my life is about nothing else... The quality common to the three experiences... is that of an unsatisfied desire which is itself more desirable than any other satisfaction. I call it Joy, which is here a technical term and must be sharply distinguished both from Happiness and Pleasure. Joy (in my sense) has indeed one characteristic, and one only, in common with them; the fact that anyone who has experienced it will want it again... I doubt whether anyone who has tasted it would ever, if both were in his power, exchange it for all the pleasures in the world. But then Joy is never in our power and Pleasure often is.”
― C.S. Lewis, Surprised by Joy: The Shape of My Early Life