Recent discussion of Vogel-style “bootstrapping” scenarios suggests that they provide counterexamples to a wide variety of epistemological theories. Yet it remains unclear why it’s bad for a theory to permit bootstrapping, or even exactly what counts as a bootstrapping case. Going back to Vogel's original bootstrapping example, I note that an agent who could gain justification through the method Vogel describes would have available a “no-lose investigation”: an investigation that can justify a proposition but has no possibility of undermining it. (...) The main suggestion of this article is that an epistemological theory should not permit no-lose investigations. I identify necessary and sufficient conditions for such investigations, then explore epistemological theories that rule them out. If we want to avoid both skepticism and no-lose investigations, we must eschew either Closure or epistemic externalism. (shrink)