A right good knight, and true of word ywis.Spenser.
The common form iwis was often written with the prefix apart from the rest of the word and capitalized, as, I wis, I wisse, etc. The prefix was mistaken for the pronoun, I and wis, wisse, for a form of the verb wit to know. See Wis, and cf. Wit, to know.
Our ship, I wis,Longfellow.
Shall be of another form than this.