Hitting the Books: How our lying eyes trick the brain into seeing motion during movies

Visual media has come a long way since the first proto-human cave dwellers used the flickering of torch light to bring the hand-drawn art on their walls to life. Today, the pixel -- despite its humble, low-resolution origins -- sits as the current pinnacle of digital display technology. In his new book, Biography of the Pixel, Pixar co-founder Alvy Ray Smith examines the fascinating history and development of picture elements (hence "pix"-"el") from their often-contested start in the labs of pioneering computer researchers like Alan Turing to their ubiquitous presence in modern life. In the excerpt below, Smith takes a look at the bad old days before digital displays to explain the science behind our brain's' ability to perceive motion through the rapid flashing of static images. What did the inventors of cinema do (or not) to make the system they gave us so non-ideal?