Desire, by CS Lewis

'If I find in myself a desire which no experience in the
world can satisfy, the most probable explanation is that
I was made for another world. If none of my earthly
pleasures satisfy it, that does not prove that the universe
is a fraud. Probably earthly pleasures were never meant
to satisfy it, but only to arouse it, to suggest the real
thing. If that be so, I must take care, on the one hand,
never to despise, or to be unthankful for, these earthly
blessings, on the other hand, never to mistake them for
something else of which they are only a kind of copy,
or echo, or vestige. I must keep alive in myself the
desire for my true country, which I shall not find till
after death; I must never let it get snowed under or
turned aside: I must make it the main focus of life to
pass on to that country and to help others do the same.'
(CS Lewis Mere Christianity)