An exceedingly complicated and controversial question! Some have argued that you only need epistemology, or even that epistemology is all you can get; you can only know what you can know, so you might as well confine your attention to the knowable, and not worry whether there might be things that are which are not knowable. Others claim that it's obvious that whether things exist or not surely doesn't depend on whether they're known, and it's even less likely that it could depend on such a suspicious, hypothetical property as knowability. Of course, the... (read more)