Why You Should Believe in the Digital Afterlife
Imagine scanning your Grandma’s brain in sufficient detail to build a mental duplicate. When she passes away, the duplicate is turned on and lives in a simulated video-game universe, a digital Elysium complete with bingo, TV soaps, and knitting needles to keep the simulacrum happy. You could talk to her by phone just like always. She could join Christmas dinner by Skype. E-Granny would think of herself as the same person that she always was, with the same memories and personality—the same consciousness—transferred to a well regulated nursing home and able to offer her wisdom to her offspring forever after.
And why stop with Granny? You could have the same afterlife for yourself in any simulated environment you like. But even if that kind of technology is possible, and even if that digital entity thought of itself as existing in continuity with your previous self, would you really be the same person?
As a neuroscientist, my interest lies mainly in a more practical question: is it even technically possible to duplicate yourself in a computer program? The short answer is: probably, but not for a while.
Let’s examine the question carefully by considering how information is processed in the brain, and how it might be translated to a computer.
The first person to grasp the information-processing fundamentals of the brain was the great Spanish neuroscientist, Ramon Y Cajal, who won the 1906 Nobel Prize in Physiology. Before Cajal, the brain was thought to be made of microscopic strands connected in a continuous net or ‘reticulum.’ According to that theory, the brain was different from every other biological thing because it wasn’t made of separate cells. Cajal used new methods of
