Barnum’s financial logic begins with a single rule: income must exceed expenditure, enforced not by penny-pinching but by systematic awareness of where money goes. The second pillar is the avoidance of debt, which reverses the arithmetic by making compound interest work against the borrower. The third is the insistence that capital must be self-earned, because the discipline acquired in earning is itself the education that makes keeping money possible. Together these three principles form the financial substratum beneath every other strategy Barnum recommends.