 Because it is not foundationalist in these ways, reflective equilibrium also avoids some other problematic distinctions or claims that are part of an effort to show how some beliefs can be directly justified or warranted. For example, some foundationalists view particular moral judgments as fixed; others might think it is our moral principles or some deeper theoretical beliefs from which such principles might be derived that are fixed and unrevisable. Some proponents of both approaches have even claimed that a moral sense or faculty reveals these directly justified beliefs to us. For others, we can discover the foundational beliefs in some deep moral belief structure that is revealed to us through a careful examination of moral judgements and that is arguably a priori. A considerable part of contemporary work in substantive ethics treats appeals to moral intuitions or considered judgments in this way (Thompson 1976, McMahan 2000, G.A. Cohen 2007). Some who work in this fashion cite Rawls (1974) when they embrace reflective equilibrium. We return to the topic of intuitionism again later in this entry.