Her honour is an essence that’s not seen;
They have it very oft that have it not.
But, for the handkerchief, –
– William Shakespeare
Othello, Act 4, Scene 1. Iago is speaking to Othello about Desdemona’s honor and the honor of women in general. The theme of appearance vs reality appears here, as Iago says that Desdemona’s honor is something that cannot be seen. Often people appear to be honorable, but they are not, he suggests. He then cleverly mentions Desdemona’s missing handkerchief, something that can be seen. He is manipulating Othello into thinking about the handkerchief.