The Etymology of Advice
Advice is, at its root, about seeing. The word descends from Old French avis, which crystallised from the phrase ce m'est a vis — 'it seems to me', literally 'this is to my sight'. That vis comes from Latin visum, the past participle of videre ('to see'), the same root behind 'vision', 'video', 'visa', and 'visible'. Giving advice originally meant sharing your view of a situation, your way of seeing it. English borrowed the word in the thirteenth century from Anglo-Norman, initially using it to mean 'opinion' or 'consideration' before it narrowed to 'guidance on what to do'. The noun-verb spelling split — 'advice' with c, 'advise' with s — follows the same pattern as 'device/devise' and 'practice/practise', a convention English formalised in the fifteenth century to distinguish the thing from the action.