Both Jeremy Bentham and John Stuart Mill were philosophers who wrote on the ethical theory of Utilitarianism. Briefly discuss the most significant difference between Mill's Utilitarianism and Bentham's Utilitarianism.

Both Jeremy Bentham and John Stuart Mill were philosophers who wrote on the ethical theory of Utilitarianism.  Briefly discuss the most significant difference between Mill’s Utilitarianism and Bentham’s Utilitarianism.