In The Duchess of Malfi, in which instances does Bosola show that there is indeed some good in him or do we presume he is ultimately sinful?
In The Duchess of Malfi, the audience has no misconceptions about Bosola, the malcontent, released from prison despite his part in a vicious murder. Bosola is not happy with his status in life and is determined to better himself at all cost, failing to recognize his own contribution to his misery to the point that, as Antonio points out, he will "poison all his goodness." The totally contrasting and conflicted nature of Bosola, his ability to convince the Duchess that he can be trusted and his belief that he is just "the bellman" in all the schemes and murders, confirms his shallow nature and his insular personality.
Bosola is aware of the duplicity of the society to which he belongs and uses it to his advantage. Initially impressed by the Duchess as she sees value in a person regardless of their social standing and "merely for worth...," he still spies on her on behalf of her brothers. His character supports the theme of appearances as compared to reality and, although his character develops and his perception changes, it is not sufficient for him to actually rise above his wickedness in order to prevent further tragedy.There are a few acts of kindness that Bosola seemingly, carries out but ultimately, he sees no purpose in good deeds as they always backfire, on him, particularly. He realizes that the Duchess and Antonio have real meaning in their relationship and that being a good servant by spying on the Duchess has done anything but make him a good man. In order to redeem himself, he intends to kill Ferdinand but mistakenly, kills Antonio. Just before his own death, he reflects on the "deep pit of darkness," in which everyone must exist. It is small consolation to him that Ferdinand and the Cardinal are dead.