“Everything but happiness is neurosis.”

Attributed

Not a Kerouac quote, but by the Indian spiritual leader, Sri Chinmoy (1931-2007).
Misattributed

Source: Morality for Beautiful Girls

Prelude to Pt. I, st. 7
The Vision of Sir Launfal (1848)
Context: Joy comes, grief goes, we know not how;
Everything is happy now,
Everything is upward striving;
'Tis as easy now for the heart to be true
As for grass to be green or skies to be blue,—
'Tis the natural way of living:
Who knows whither the clouds have fled?
In the unscarred heaven they leave no wake;
And the eyes forget the tears they have shed,
The heart forgets its sorrow and ache;
The soul partakes the season's youth,
And the sulphurous rifts of passion and woe
Lie deep 'neath a silence pure and smooth,
Like burnt-out craters healed with snow.

The Basic Teachings - Part 1: Principles of the Teaching (2009)

Ibid., p. 328
The Book of Disquiet
Original: Não há felicidade senão com conhecimento. Mas o conhecimento da felicidade é infeliz; porque conhecer-se feliz é conhecer-se passando pela felicidade, e tendo, logo já, que deixá-la atrás. Saber é matar, na felicidade como em tudo. Não saber, porém, é não existir.