Mill famously argued that the ethical action is what leads to the greatest amount of happiness for the greatest number of people. Please write an essay about Mill's utilitarian ethical theory that answers the following questions:
1. Does utilitarian theory require us to--somehow--have certain knowledge about the future? Can we identify which actions will cause the greatest amount of happiness for the greatest number of people without having certain knowledge of the future?
2. Can a utilitarian consistently reject as immoral the enslavement of a small group of people whose enslavement brings great happiness to a much larger group of people?
3. Do either of these two problems (the 'knowing the future' problem and the 'justification of slavery' problem) mean that utilitarianism is an unsatisfactory ethical theory? Why or why not?