FEO might be adopted in conjunction with formal equality of opportunity or by itself as a freestanding moral requirement. The difference between FEO alone and FEO paired with formal equality of opportunity emerges when one pictures a society that satisfies FEO but not formal equality of opportunity. A society might be composed equally of members of two hostile groups, who discriminate against each other at every opportunity. If the groups command the same amount of economic resources, it could happen that formal equality of opportunity is always violated, because in every context of interaction people favor members of their own group regardless of their qualifications. If men discriminate against women, and women against men, these effects might counterbalance so that freestanding FEO is still satisfied. The following discussion of FEO for the most part interprets it as an inclusive doctrine containing formal equality of opportunity.