This is what the philosopher Nelson Goodman called the riddle of induction: We project a straight line only because we have a linear model in our head—the fact that a number has risen for 1,000 days straight should make you more confident that it will rise in the future. But if you have a nonlinear model in your head, it might confirm that the number should decline on day 1,001.
Induction works if straight lines work. Specific to general Ducts are straight. That is unless they aren't. How about, in the beginning I used a theory to predict a future.
