“This time is different” in one fundamental, methodological, epistemological way: we test on the training set now. This has follow-on consequences for a shatte

“This time is different” in one fundamental, methodological, epistemological way: we test on the training set now. This has follow-on consequences for a shattering phase transition between “persuasive demo” and “useful product”. We can now make arbitrarily convincing demos that will crash airplanes (“with no survivors!”) on the first try in production. This is institutionalized by the market capitalizations of 7 companies being so inflated that if they were priced accurately the US economy would collapse.