The capacity to make progress is the most basic feature of rationality. An adequate conception of progress requires a goal and clear criteria for moving towards and away from the goal. This, in turn, defines an agent as, respectively, more and less rational. The goal may be specified as a dimension, such as income per capita or the ratio of true beliefs, in which increases and decreases can be registered over time. Crucially, in the course of its pursuit, the goal of progress must either be fixed or else changed explicitly. The problem with most conceptions of progress is that they meet neither of these conditions. Rather, goals are subtly shifted as they are pursued. Often substantially different (or incommensurable) goals are discussed in largely the same terms, so that the shifts are not readily apparent. This gives rise to instances of adaptive preference formation, whereby people come to adjust their goals to match their expectations: they come to want what they are likely to get. Fuller's version of social epistemology has consistently drawn attention to this feature of collective memory (see common sense versus collective memory), which appears especially in acts of translation, in which people from the past are interpreted as having said things that justify current orthodoxies as the most advanced stage towards goals that have always been pursued.