 A second externalist approach can be offered either as an alternative or an addendum to reliabilism. It holds that what makes certain beliefs about the world justified is that they have a distinctive psychological etiology, e.g., that they are the outputs of a perceptual module (where what counts as a perceptual module is spelled out in architectural terms, rather than in terms of phenomenology or the agent’s background beliefs; Lyons 2009). Psychological etiology is not available to mere reflection, and the theory leaves open the possibility that the agent has a justified perceptual belief with the requisite perceptual etiology, without having any conscious experiences or evidence of any other kind. Obviously, the lack of an evidential requirement will be controversial, but the proponent of this view sees this as little more than the externalist had already signed on for.