Over the years we have sometimes had debates over how important it is to study physics and biology and epistemology (the canon). Some - primarily the anesthesiologists - say knowledge in those areas is not important, but I think that's a laughably silly suggestion. Of all people, Epicureans are MOST in need of knowledge in a broad spectrum of areas, because we do not rely on gods or absolute idealistic standards to tell us what to do. For the Epicurean, the test of every choice, every action, is "What will happen to me if I choose this course of action and what will happen to me if I don't?"
Accurate predictions about the future results of our courses of actions are hard enough even with a broad knowledge of Natural Science, of Humanity, and of History. Without knowledge in those areas, no accurate predictions about the future are possible at all.
As recorded from Epicurus himself, the rule is: PD71. "Question each of your desires: 'What will happen to me if that which this desire seeks is achieved, and what if it is not?'"