Epistemic blank checks and the heat death of the universe

Phenomenal conservatism is the view that if something seems true to you, you are justified in believing that it is true so long as there isn’t sufficient reason to believe otherwise. For instance, a moral realist may say that we have prima facie justification for believing that things are how they seem. It seems to them that moral realism is true, so they're justified in believing moral realism is true unless you present sufficient arguments to the contrary.

This looks, at first glance, like an epistemically modest principle. If seemings consistently provided a little evidence, just enough to get you started, or to settle a tie, perhaps they can serve in such a role. The proponent of phenomenal conservatism is admitting the fallibility of their position: they could, in principle, be proven wrong. In fact, a belief held merely on the basis of it seeming to be true seems to rest on very tenuous footing. It could be easily overturned the moment any moderately persuasive rebuttal comes alo…