The Flynn effect covered up the dysgenic trend that has been steady for a long time--probably since 1800 in the West. That effect is played out and we will see

The Flynn effect covered up the dysgenic trend that has been steady for a long time--probably since 1800 in the West. That effect is played out and we will see a steady reduction from now on, assuming no major social changes. The Flynn effect itself was likely caused by a combination of nutrition, access to early education, and (simply put) a familiarity with IQ test formats. I never see people mention the latter, but imagine someone from 1932 being presented with an IQ test. The very process (3d shapes, analogies, numbers backwards?) would have been baffling for 100 percent of recipients.