For some reason this made me think of the problems with side effects in programming. If we can read and write willy-nilly, it’s very difficult to figure out why the data is the way it is, and we can’t undo/rewind unless we planned for it all along.

When our minds are mulling over some piece of information, whether it’s true or not, it will have side effects on other thoughts, opinions and emotions. If we’re confronted with a revised set of facts later, there is no way to rewind all those side effects.