Let us have done with vain regrets and longings for the days that never will be ours again. Our work lies in front, not behind us; and “Forward!” is our motto. Let us not sit with folded hands, gazing upon the past as if it were the building; it is but the foundation. Let us not waste heart and life thinking of what might have been and forgetting the may be that lies before us. Opportunities flit by while we sit regretting the chances we have lost, and the happiness that comes to us we heed not, because of the happiness that is gone.

Jerome K. Jerome (1859-1927) English writer, humorist [Jerome Klapka Jerome]
Idle Thoughts of an Idle Fellow, “On Memory” (1886)
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First published in Home Chimes (1885-09-26).