Willingness to Sacrifice in Diagnostic Situations: The Intersection of Interdependence Theory and the Self-Expansion Model

Diagnostic situations, in which an individual's own interests are incompatible with those of their partner, appear to propose a dilemma for the concurrence of interdependence theory and the self-expansion model. On the one hand, interdependence theory suggests that sacrifice in such situations involves a transformation of motivation, whereby one's immediate, automatic reaction is selfish, and only with sufficient commitment and time for reflection might it transform to a desire to maximize joint outcomes (Aron & Aron, 2010; e.g., Yovetich & Rusbult, 1994). However, the self-expansion model asserts that close others are in fact included in the self so that, to an extent, one's primary "gut" reaction to a diagnostic situation would be to consider one's partner's outcomes as one's own (e.g., Aron et al., 1991, Study 1). The present study manipulated the extent to which one's partner was included in the self and revealed that high self-other inclusion and commitment were both associated with greater willingness to sacrifice. Surprisingly, manipulation of response time revealed that participants who were given unlimited time to respond to diagnostic situations were less likely to sacrifice than those who had limited time. Finally, the effect of commitment on willingness to sacrifice was strongest in the low self-other inclusion group, suggesting that, for those individuals who feel less overlap with their partners, sufficient commitment may still facilitate relational sacrifice by resulting in a transformation of motivation