How does Shakespeare present manipulation through Iago in Othello?

Iago manipulates other characters throughout the play to the point where by the end he has destroyed their lives using only words. Iago represents temptation and an appeal to the darker side of human nature. He doesn't commit the deeds himself but merely plants the notion in the minds of others. The very word "Iago" actually means "the planter."

He notices Cassio's weakness for alcohol and plays on this. Like true temptation, he does not...

Iago manipulates other characters throughout the play to the point where by the end he has destroyed their lives using only words. Iago represents temptation and an appeal to the darker side of human nature. He doesn't commit the deeds himself but merely plants the notion in the minds of others. The very word "Iago" actually means "the planter."

He notices Cassio's weakness for alcohol and plays on this. Like true temptation, he does not create this weakness or force anyone to act on it. He merely finds the weakness and presses on it. This is the way that manipulation works, the way the devil might work. He tips emotions in this particular direction.

He later plays on Othello's jealousy and rage by hinting that Desdemona might be unfaithful. Yes, he creates scant signs of evidence, but truly all he is doing is awakening Othello's existing weaknesses. A calmer and less jealous man would calmly confront his wife and then believe her when it became clear there was very little evidence. The genius of Iago's manipulation is his ability to identify existing weaknesses in others and then press on them to achieve a tragic outcome.

These tragic manipulations are an exploration of human coercion, but are also a much deeper look at human fragility in the face of our darker nature.