This experiment explores whether individuals know that other people are biased. We confirm that overestimation of abilities is a pervasive problem, but observe that most people are not aware of it, i.e. they think others are unbiased. We investigate several explanations for this result. As a first one, we discuss a possible unfamiliarity with the task and the subjects' inability to distinguish between random mistakes and a real bias. Second, we show how the relation between a subject's belief about others and his belief about himself might be driven by a false consensus effect or self-correction mechanism. Third, we identify a self-serving bias when comparing how a subject evaluates his own and other people's biases.