iago must ensure that roderigo does not incontinently down (303) himself. he needs him. look to lines 331-356 and list an argument he uses to ensure roderigo remain patient and courageous in his attempt to win desdemona.
Iago calls Riderigo a coaward and a "baboon" for drowning himself over a woman,
I would say I would drown myself for the love of a guinea hen, I would change my humanity with a baboon.
Iago says that Roderigo suffers from lust but has the gift of human reason to counter it:
But we have reason to cool our raging motions, our carnal stings, our unbitted lusts. Whereof I take this that you call love to be a sect or scion.
