Typicality: Stable structures and flexible functions.

Some research suggests typicality is stable, other research suggests it is malleable, and some suggests it is unstable. The two ends of this continuum-stability and instability-make somewhat contradictory claims. Stability claims that typicality is determined by our experience of decontextualized feature correlations in the world and is therefore fairly consistent. Instability claims that typicality depends on context and is therefore extremely inconsistent. After reviewing evidence for these two claims, we argue that typicality's stability and instability are not contradictory but rather complementary when they are understood as operating on two different levels. Stability reflects how information gets encoded into semantic memory-what we call structural typicality. Instability reflects the task-dependent recruitment of semantic knowledge-what we call functional typicality. Finally, we speculate on potential factors that may mediate between the recruitment of structural or functional typicality.