 This
plot of course would not work Othello’s “soul” were not “so enfettered to her love”—if Othello was not
so passionate about having Desdemona (2. 3. 365). At this point Iago’s plot is relatively airtight, his
advice is “Probal to thinking” and there is not really anyone who can discover his plot until his wife
picks up the handkerchief Othello gave Desdemona. Because of Othello’s passion for Desdemona, this
plan works very well, Othello is “moved” (3. 3. 254) when Iago even hints of his suspicions, Othello is
later “eaten up with passion” (3. 3. 446) when Iago continues to hint of and plant images of Cassio and
Desdemona’s alleged affair.
Othello’s passion takes over when Iago hits a heartfelt subject: the handkerchief that was his
first gift to Desdemona. When Othello first hears of the handkerchief, he immediately commands his
“black vengeance” to “arise” (3. 3. 507) and this point is where Othello claims that his “bloody
thoughts ... / Shall ne’er look back” (3. 3. 518-519). At this point Othello does not even have proof
besides Iago saying so that Cassio has the handkerchief, and even if he did, Cassio’s possession of the
handkerchief would hardly be proof of an affair, but Othello is just so attached to Desdemona and the
handkerchief he gave her he jumps to his conclusion. As Iago brings forth more unproven accusations
that do not contain any supporting evidence, Othello begins to go mad—he cannot even talk in full
sentences: “Confess—handkerchief—O, / devil!” (4. 1. 50) and falls “into an epilepsy” (4. 1. 61). The
hardest evidence Othello ever gets of the alleged affair is when he watches Cassio display “the
handkerchief” as he laughs and talks about some unknown topic with Iago (4. 1. 192). This is hardly a
very good deception by Iago since Cassio and Iago will be discussing a completely different person
than Othello thinks, Iago even admits that Othello’s “jealously must construe / Poor Cassio’s smiles,
gestures, and light behaviors / Quite in the wrong” (4. 1. 118-120). Othello is so overtaken by his
passion, his anger at Desdemona because of what he thought she did with Cassio, when Emilia admits
she has “seen nothing ... / Nor ever heard, nor ever did suspect” the statement barely even registers (4.
2. 1-2). Even when Desdemona herself admits that she is Othello’s “true and loyal wife” (4. 2. 41) and
that “Heaven doth truly know it” (4. 2. 47), Othello is still so angry he still believes she is “false as
hell” (4. 2. 48). Even after Othello kills his wife and discovers the whole horrible truth of how he was
deceived, the first conclusion he comes up with “loved not wisely” (5. 2. 404).
Ultimately, the fact that the cause is in the end Othello’s passion becomes evident. 
