How can People be Dumber Today than in Ancient Times?

Humans lost a lemon sized portion of their brain in recent millenia.

Modern people who believe in linear historical progress (a concept that was invented by Francis Bacon in the 1600s) cannot believe that they are actually dumber than a "caveman". Cavemen didn't have technology or science, which start in the 1600s by the way.

Do modern people create technology or science? No. 99% of modern people do not create technology or science. They use technology, and some can barely manage that. They mistake the existence of technology and culture for everyone being involved in its creation.

Several thousand years ago every family had to be a family of MacGyvers. Every family member had to know how to do everything to survive. If you weren't a MacGyver, you just died if you lost family support. That was the human condition for a very long time.

Eventually, those MacGyvers realized they could reduce the difficulty level of life by storing seeds in jars and living in buildings that they MacGyvered into existence. Those innovations made it possible for dumber people to survive. That process continued for thousands of years. The average person is dumber today than 100 years ago, and he was dumber than the average person 1000 years ago.

Belief in linear progress based on science and technology permeates the society and allows the dumb people to imagine they're really smart because they are alive in the present moment rather than 200 years ago.