 Second, the idea that the best science is that which eliminates bias evokes an ideal of science as value-free—that is, free from moral, cultural, or political values. While this conception of science dominated philosophy of science in the first half of the twentieth century it has since been challenged. The extent to which values may play a legitimate role, when, and in what aspects of science, has been extensively explored during the past few decades (see  feminist epistemology and philosophy of science—section  7, also Lacey 1999; Kincaid, Dupré, &amp; Wylie 2007; Elliott 2017). Feminist philosophers of science have been active participants in this discussion.