Soliloquies are provided by the play-write to reveal to the audience what the innermost thoughts and feelings are of the character speaking. In this passage, Othello has just been advised by Iago to sit and watch his wife Desdemona as she socializes with Cassio. Othello's tragic flaw is being too trusting with Iago and praises his mentor by saying, "This fellow's of exceeding honesty,/ And knows all qualities with a learned spirit,/ Of human dealings" (263-265). In order to move the plot forward, Shakespeare uses this soliloquy to identify Othello's confusion about the matter and the battle he has within himself as to whom he should trust more--his wife, himself, or Iago. This moment shows Othello as vulnerable and easily manipulated. Fortunately for Iago, it is right after this soliloquy that his wife Emilia obtains the handkerchief that will be used as a tool to further deceive Othello into believing he is a cuckold.