Save like a pessimist, invest like an optimist
I’m skeptical of the closing claim that exponential growth keeps happening forever. Yes, you can grow GDP 2% for 200 years, that results in an economy 50x the start size. Expand it to 1000 years and you’re talking about an economy 400 million times as large. After 2100 years you’re up to an economy a QUINTILLION times as large.<p>At some point the exponential curve has to go S-shaped. Maybe we’re still in the happy exponential looking part of the curve. There are also signs we might be transitioning. Population growth has slowed, productivity growth has slowed, and the marginal return on capital seems to be somewhere around zero given modern interest rates.