I loved this, as it happens that in the essay I am working on, I wrote about four great inventions that have shaped the course of humanity.
The first invention was language. It allowed the forebrain to construct an understanding of reality that transcended the senses. The wisdom gained was limited by the capacity of a single brain, and had to be passed on orally.
The second invention was writing. The totality of knowledge was no longer limited to being memorized.
The third invention was the printing press. No longer were those ideas the province of an elite few. Everybody could read or hear about them and contribute to the body of knowledge.
The fourth invention is the internet. This has a number of effects, including access to information and problems with its veracity. One important power of the internet is that people everywhere can connect and see each other as human.