Human intelligence is based on language
Language provides superior communication. Humans are the most communicative species, and we interact very closely by language from birth. Essentially, in this way, humans are an extremely socially connected species — and therefore very powerful. Humans have developed this only very recently, when modern humans appeared, 40,000–100,000 years ago.
Language is a method for closely linking our brains together with intensely structured sounds reaching into the whole cortex and most subcortical areas. Humans speak and listen very fast, they hold a speed record for auditory neurons among animals. — Everything followed in evolution from making a decisive conceptual leap from simple object naming to sentence construction — probably built on mutations that we do not yet fully understand. Humans are much more closely linked than any ant hive and this need is so great that we developed ever more tools for extending our social connections — writing and calculating, printing, radio, computing, the internet, and so on.
Human intelligence is special, but it is entirely social, even for the lone individual who reads books, and solves problems using the language they learned as children from others. There could be other ways to develop intelligence, but there is an important lesson here for AI as well. We do not model single brains to understand human intelligence, we need to model their interaction.
