17. See Carol Gilligan, In a Different Voice: Psychological Theory and Women’s Development (Cambridge, MA: Harvard University Press, 1993). Gilligan’s book took on the highly influential work of Laurence Kohlberg, who outlined “stages of moral development.” Kohlberg concluded that males generally reached a higher level of moral development than females, but Gilligan argued that Kohlberg’s definitions privileged the kind of moral reasoning done by males rather than females. For Kohlberg, the highest level of moral development is a “personal moral system based on abstract principles.” This will leave women out, Gilligan argued, because men indeed do tend to inform their judgment of “right” and “wrong” by reasoning from abstract principles, while women tend to judge them on the basis of personal relationships, on the basis of compassion and empathy. This has been called “difference feminism” by some.