“Everything is perfect on the street again, the world is permeated with roses of happiness all the time, but none of us know it. The happiness consists in realizing that it is all a great strange dream.”

Haunted (2005)
Variant: I used to think the secret to a happy ending was to bring down the curtain at the exact right time. A moment after happiness, then everything's all wrong, again.

Source: This Side of Paradise

The Jewel of Seven Stars, Chapter XIX: The Great Experiment (1903)

Source: The Sisterhood of the Traveling Pants

"April", in Poems (1859)
Context: Awakener, come!
Fiing wide the gate of an eternal year,
The April of that glad new heavens and earth
Which shall grow out of these, as spring-tide grows
Slow out of winter's breast.
Let Thy wide hand
Gather us all — with none left out (O God!
Leave Thou out none!) from the east and from the west.
Loose Thou our burdens: heal our sicknesses;
Give us one heart, one tongue, one faith, one love.
In Thy great Oneness made complete and strong —
To do Thy work throughout the happy world —
Thy world, All-merciful, Thy perfect world.

Letter to his mother, written from the University of Pennsylvania (12 February 1904), published in The Selected Letters of William Carlos Williams (1957) edited by John C. Thirlwall, p. 5
General sources

The Final Declaration (1954)
Context: For man to have a glimpse of lasting happiness, he has first to realize that God, being in all, knows all; that God alone acts and reacts through all; that God, in the guise of countless animate and inanimate entities, experiences the innumerably varied phenomena of suffering and happiness. Thus, it is God who has brought suffering in human experience to its height, and God alone who will efface this illusory suffering and bring the illusory happiness to its height.

Source: Summa Theologica (1265–1274), I–II, q. 3, art. 8 co

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