Humans process positive information and negative information differently. These valence asymmetries in processing are often summarized under the observation that ‘bad is stronger than good’, meaning that negative information has stronger psychological impact (e.g., in feedback, learning, or social interactions). This stronger impact is usually attributed to people’s affective or motivational reactions to evaluative information. We present an alternative interpretation of valence asymmetries based on the observation that positive information is more similar than negative information. We explain this higher similarity based on the non-extremity of positive attributes, discuss how it accounts for observable valence asymmetries in cognitive processing, and show how it predicts hitherto undiscovered phenomena.