The Visual Cliff Psychology Experiment | Plainly Difficult Documentary

https://invidious.fbxl.net/watch?v=oK1UgqHz7_U

A relevant passage from The Graysonian Ethic: "In a lot of ways you do not realize, the human race is entirely defined by our biology. Many of your deepest-rooted fears and ambitions are written into your blood, in a library that was passed down by millions of generations of successful creatures going all the way back to the single celled organisms that first spawned within the primordial ooze."