For a host of reasons, training students and teachers to more accurately discern the thoughts, feelings, and motivations of others is more important than ever. One approach to improving social perspective taking entails teaching students to understand when and how bias impedes their efforts to "read" others. To facilitate this educational goal, we propose a theory of meta-biases that unifies and distills those biases that frequently derail perspective taking attempts. Specifically, we argue that, as a default, people strive to accurately read themselves and others. However, two competing motives--meta-biases--often derail this default goal: a desire for cognitive efficiency and a need to protect or enhance one's sense of self. We hope the proposed theory proves to be practical for educators trying to facilitate interpersonal understanding and relationships, stimulating for researchers interested in testing theory, and generative for anyone developing interventions to mitigate social cognitive biases and improve person perception attempts.