故
コ, ゆえ, ふる.い, もと

happenstance, especially, intentionally, reason, cause, circumstances, the late, therefore, consequently

JLPT1 G5 S9 F612

古# hard; dried out + 攵 action indicator → harden into fixed reality → *old*; *die*; *the late* (referring to a deceased person) → *old acquaintance*; *reason*; *cause*; *circumstances*; *past* (← by reason of past circumstances ← stand firm upon established premises, for example, "because such and such is so, therefore X").

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