I recently started reading up on the standard approaches to epistemology. Much of the primary discussion seems to be focused on the question "what constitutes knowledge?". The basic definition used to be that to count as knowledge it needs to be a belief, it needs to be justified, and it needs to be true. But there's the Gettier Problem which points out that there are cases that satisfy the above criteria but which we wouldn't normally consider "knowledge". Numerous alternative "theories of knowledge" have been proposed, new counter-examples have been pointed out, philosophers have split into competing camps (each under its own "-ism" title), and hundreds if not thousands of papers have been published on this topic.

But I'm totally confused. It sounds like they're just arguing about basically arbitrary definitions. So agree on a definition and get on with it. Or define different types of knowledge if that suits you better. And if that doesn't perfectly capture everything we might mean by the word "knowledge", what difference does it make? If they'd taboo the word "knowledge" would there be anything left to discuss?

I assume I'm just missing something. But if in fact they could just taboo the term and get on with more important discussions, then could someone please explain to me why so many highly intelligent, extremely thoughtful philosophers have spent so much time on a (seemingly) ridiculous discussion?