An Etymological Dictionary of the German Language/Annotated/wissen
wissen, verb, ‘to know, beware of,’ from the equivalent Middle High German wiȥȥen, Old High German wiȥȥan; a common Teutonic, and more remotely a primitively Aryan preterite present. Compare Gothic wait, ‘I know,’ Anglo-Saxon wât, English wot, Old Saxon wêt, Old High German and Middle High German weiȥ. Based on pre-Teutonic woid, wid, in Sanscrit vêda, ‘I know,’ Greek οἶδα, Old Slovenian vĕděti, ‘to know.’ This primitively unreduplicated perfect is based on a root wid, which in the Aryan languages means literally ‘to find,’ then ‘to see, recognise’; compare Sanscrit vid, ‘to find,’ Greek ἰδεῖν, Latin videre, ‘to see,’ Gothic witan, ‘to observe.’ In German compare gewiß, verweisen, weissagen, Witz.