From the poem "To A Mouse" by Robert Burns:
Still thou are blest, compar'd wi' me!
The present only toucheth thee:
But Och! I backward cast my e'e,
On prospects drear!
An' forward, tho' I canna see,
I guess an' fear!
Burns says the mouse is actually luckier than he is. The mouse only lives in the present. Humans, however, look back at the past with regret ("prospects drear") and look toward the future with "guess and fear."
