1408: Development of Affirmation in Romance Languages

Latin doesn't really have a word for 'yes', and yet modern Romance language that descended from Latin do. In Spanish the word 'sí' and in Italian the very similar 'sì' also means 'yes', but the former comes from the Latin 'si' meaning 'if' and the latter derives from the Latin 'sīc (est)' meaning 'thus (it is)', so are therefore unrelated. Moreover, in French, 'oui' comes from 'hoc' meaning 'that', and moreover Occitan uses the word 'òc'; likewise the Portuguese 'isso' also comes from a Latin word for 'that', but a different one. In this way, Spanish and Italian's words for 'yes' sound the closest but are really not at all related. The etymology of the Romanian 'da' is debated, with some saying it is from a Slavic origin while others say it comes from the Latin 'ita' which means 'therefore'. As you can see, none are really from the same origin even though they (may) all be from Latin.