OK, good for you. Many or even most people would just spend the extra money, not "put [it] in the market and earn significantly more than my mortgage rate." Th

OK, good for you. Many or even most people would just spend the extra money, not "put [it] in the market and earn significantly more than my mortgage rate." The default rates after the 2008 crash proved that. EDIT: The parent post is a modern sophisticated financial theory, and it's absolutely correct. Your great-grandparents, who lived through the Depression, might have a much different take: "Debt is bad. Do not have any debt." That's irrational, for sure. It probably resonates with you on some level, though.