A long time ago, in this galaxy, near-primordial savages across parts of Eurasia were using the word men to describe the action of "thinking". This Proto-Indo-European term went into Ancient Greek as mnestis, which changed slightly, semantically, as it took on a meaning of "remembering". This may seem familiar, because when added to the prefix a- ("not"), the word becomes amnestos, or "forgotten". This is connected to the word amnesty through Latin amnestia and French amnestie, and makes sense because in an amnesty the past crimes of a person are forgiven by whoever is doing the pardoning. Meanwhile, the Greeks made the word amnesia, also from the a- prefix and a conjugated form of mnestis, to create a word that meant something more along the lines of "forgetting" than "forgotten". Amnesty entered English two hundred years before amnesia.
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.