I think the trigger event for modern consciousness mode is a critical percent of population being literate. It could been happening a few millenia earlier than

I think the trigger event for modern consciousness mode is a critical percent of population being literate. It could been happening a few millenia earlier than his book suggests, and shaped the brain around reading the "fixed language"(i.e. written words) allowing abstraction levels not possible with earlier purely verbal communication. https://en.wikipedia.org/wiki/Reading_(process)#History https://en.wikipedia.org/wiki/Reading_(process)#History The history of reading dates back to the invention of writing during the 4th millennium BC. Although reading print text is now an important way for the general population to access information, this has not always been the case. With some exceptions, only a small percentage of the population in many countries was considered literate before the Industrial Revolution. Some of the pre-modern societies with generally high literacy rates included classical Athens and the Islamic Caliphate.[41] Scholars assume that reading aloud (Latin clare legere) was the more common practice in antiquity, and that reading silently (legere tacite or legere sibi) was unusual.[42] In his Confessions, Saint Augustine remarks on Saint Ambrose's unusual habit of reading silently in the 4th century AD.[42][43]