the.com/postscript

The afterthought that sometimes outshines the entire letter.

means A note tacked on after a letter's signature, added once the writer realized they weren't quite done.

from From Latin post scriptum, meaning 'written after' — post (after) plus scriptum (written), the past participle of scribere, 'to write.' It entered English through the practical habit of letter-writers who, having already signed off, found one more thing worth saying and simply wrote it below, labeling it honestly as what it was: an afterward.

origin
Latin post scriptum, written after
also means
Adobe's page-description language, PDF's ancestor
irony
often contains the actual point
psychology
readers remember last lines best
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