<prompt> Human: Where does that magic number 4 come from? As Ive started spending time on this subreddit, I see people recommend paying debt before investing, unless the debt is 4 or under. Is there a specific line of reasoning that leads to this, or is it more a rule of thumb than a hard and fast line in the sand apologies if Ive mixed too many metaphors?  <response>: Its just a guideline. It depends on your risk tolerance. 