i have wist, sin i couthe meen,
that children hath by candle light
her shadewe on the wal iseen,
and ronne therafter all the night.
bisy aboute they han ben
to catchen it with all here might.

and whome they catchen it best wolde wene,
sannest it shet out of her sight.
the shadewe catchen they ne might,
for no lines that they couthe lay.  this
shadewe i may likne aright
to this world and yesterday.

Translation:

ever since i could remember, i have known,
that children, by candle light,
have see a shadow on the wall
and have chased it all night through.
busily they have tried,
with all their might, to catch it.

and when they most expect to catch it
it shoots most quickly out of sight
this shadow never shall be caught
in any trap they lay
this shadow in the likeness
of this world and yesterday.