Peter K. Unger (/ˈʌŋɡər/; born April 25, 1942) is a contemporary American philosopher and professor in the Department of Philosophy at New York University.
In the field of applied ethics, his best-known work is Living High and Letting Die (1996).
In this text, Unger argues that the citizens of first-world countries have a moral duty to make large donations to life-saving charities (such as Oxfam and UNICEF), and that once they have given all of their own money and possessions, beyond what is needed to survive, they should give what belongs to others, even if having to beg, borrow, or steal in the process.
In "The Mental Problems of the Many" (2002), he argues for substantial interactionist dualism on questions of mind and matter: that each of us is an immaterial soul.
In Empty Ideas (2014), he argues that analytic philosophy has delivered no substantial results as to how things are with concrete reality.