  Whether implicit biases are cause for this sort of epistemic concern depends on what sort of causal influence social attitudes have on visual perception. Payne’s weapons bias findings would be a case of “cognitive penetration” if the black primes make the images of tools look like images of guns, via an effect on perceptual experience itself (Siegel 2012, 2017, forthcoming). This would certainly introduce a circular structure in belief formation. Other scenarios raise the possibility of illicit belief formation without genuine cognitive penetration. Consider what Siegel calls “perceptual bypass”: the black primes do not cause the tools to look like guns (i.e., the prime does not cause a change in perceptual experience), yet some state in the agent, such as a heightened state of anxiety, is affected by the black prime and causes the agent to make a classification error. This will count as a case of illicit belief formation inasmuch as the agent’s social attitudes cause her to be insensitive to her visual stimuli in a way that confirms her antecedent attitudes (Siegel 2012). Other scenarios might allay the worry about illicit belief formation. For example, what Siegel calls “disowned behavior” proposes the same route to the classification error as “perceptual bypass,” except that the agent antecedently regards her error as an error. Empirical evidence can help to sort through these possibilities, though perhaps not settle between them conclusively (e.g., Correll et al. 2015).