William Shakespeare - Sonnet 30:

When to the sessions of sweet silent thought
I summon up remembrance of things past,
I sigh the lack of many a thing I sought,
And with old woes new wail my dear times' waste;
Then can I drown an eye, unus'd to flow,
For precious friends hid in death's dateless night,
And weep afresh love's long since cancell'd woe,
And moan the expense of many a vanish'd sight:
Then can I grieve at grievances foregone,
And heavily from woe to woe tell o'er
The sad account of fore-bemoanéd moan,
Which I new pay as if not paid before.
But if the while I think on thee, dear friend,
All losses are restor'd and sorrows end.

William Shakespeare

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