External World Skepticism is the view that we do not have knowledge about the world around us. In reply to this view, some have argued that we should reject the sorts of skeptical challenges (e.g., that we might currently be dreaming, that we might be in the Matrix, etc.) that the skeptic suggests undermines our having knowledge. A principle like the following might be invoked:
Given a conflict between two beliefs, it is rational to reject the less initially plausible one, rather than the more plausible one.
The anti-skeptic can thus argue that my belief that there's a keyboard before me is more plausible than that my belief that I might be merely dreaming the keyboard. As a result, it's rational for me to reject the skeptical scenario (that I'm dreaming) and accept the more plausible explanation of my perceptions (that there's really a keyboard before me).
Michael Huemer suggests that this is G.E. Moore's strategy in replying to the skeptic.
I wonder what readers of this blog think of the principle above. I'm especially interested in the clause 'initial plausibility.' What, for example, entitles one to claim that my belief about there actually is a keyboard before me has more initial plausibility than my beliefs that knowledge requires the ability to rule out skeptical scenarios like that I'm dreaming or that I might be dreaming right now or that this keyboard that I seem to see might be a hallucination?