 The four-case argument attempts to show that if determinism is true, then we cannot be the sources of our actions in the way required for moral responsibility. It is, therefore, an argument for incompatibilism rather than for skepticism about moral responsibility. But, in combination with Pereboom’s argument that we lack the sort of free will required for responsibility even if determinism is false (2001: 38–88; 2014: 30–70), the four-case argument has emerged as an important part of a detailed and influential skeptical perspective. For other skeptical accounts, see Caruso (2016), Smilansky (2000), Waller (2011); also see the  entry on skepticism about moral responsibility.