  Elgesem (2008, 241) notes that search engines have an important societal role as “contributors to the public use of reason ”, and Noble (2018, 148) argues that search results can actually “structure knowledge” for the societies within which they operate. As we already noted in Section 3, Hinman (2005, 2008) and Diaz (2008) view search engines as “gatekeepers” of knowledge on the Web. Taddeo and Floridi (2016, 1575), who also describe the important “gatekeeping function” that SECs like Google now have because of their “centrality” in information societies, worry about the lack of consensus thus far with regard to which “principles should shape…[an SEC’s]…moral responsibilities and practices.” The authors argue that we need an “ethical framework” both to “define” an SEC’s responsibilities and “provide the fundamental sharable principles” necessary to guide an SEC’s conduct “within the multicultural and international context in which they operate.” But Taddeo and Floridi also believe that this problem applies to other kinds of major “online service providers,” which the authors refer to as “OSPs”; they include Facebook and Twitter as well as Google under that category. However, we limit our focus on moral-responsibility issues in this section to SECs per se.