If a super-super-duper machine was able to scan the exact physical state of your entire brain and were to recreate your brain exactly as it is in another body would there then be two of “you”? Where would “you” be?
Imagine a super-duper clever machine that can work its way through your brain and, one cell at a time, remove a cell and create a new cell in its place that is physically identical in every way. I know that the brain has a lot of cells but let’s say one cell is replaced every hour and time isn’t an issue (this is, after all, a thought experiment).
When the machine was finished, what would you experience? That you are still there or that you have gradually died?
Or would there be a crucial part of the brain in which you cannot swap even a single cell without destroying what is “you”? If so, where might this be? And would this be remedied by replacing atom-by-atom?
If you were to undergo surgery that swapped your brain with someone else’s, what would you experience after the operation?
The excellent six-part video series by Professor Daniel Dennett on consciousness.
