The effects of age-relevance of content material on reasoning were systematically studied in 120 adolescents, young adults, middle-aged adults, and older adults. Subjects were presented with either an adolescent, young adult, middle-aged, or older adult interpersonal dilemma and asked a series of structured questions assessing relativistic and dialectical assumptions. On the relativism questions, there was both a main effect of age, with highest overall performance by middle-aged and older adults, and an age by story interaction. On the dialectical questions, there was a significant age by story interaction. Subjects tended to perform most poorly on their same-aged dilemma, and the exact age trend was dependent upon the story, suggesting the role of affective processes in reasoning about emotionally relevant dilemmas. (Author)