Individuals consider abstract values and principles important aspects of their identities. Nonetheless, they often make judgments and decisions that contradict these values and principles for the sake of pragmatic benefits. Assuming that the process of weighting idealistic and pragmatic concerns is context sensitive, the present research argues that affect influences the relative weight of idealistic versus pragmatic concerns in decision situations owing to its influence on the level of abstraction at which individuals represent situations mentally. Studies 1 and 2 demonstrate that more positive affect increases the prominent weighting of idealistic over pragmatic concerns while less positive affect leads to less differentiation between the relevance of idealistic and pragmatic concerns. Studies 3 and 4 test the assumption that affective influences on mental abstraction are crucial for affect‐dependent shifts in the weighting of idealistic and pragmatic concerns. By bringing together theorizing on affect and cognition with recent theorizing on the role of mental abstraction for decision processes, this article highlights a mechanism through which decisions can be influenced by feelings that goes beyond the mechanisms that have typically been discussed in the affect and cognition literature so far.