 Additionally, some alternative ethical frameworks could also be used in analyzing ethical issues affecting search engines. These include, but are not limited to, Hans Jonas’ “Imperative of Responsibility” (Jonas 1984), Bernard Gert’s “Common Morality” (Gert 2007), and John Rawls’ “justice as fairness” (Rawls 1999). For a very brief description of how ethical aspects of search engines might also be approached from the perspectives of “rights,” “fairness,” “common good” and “virtue,” see the Markkula Center for Applied Ethics (in the Other Internet Resources).