Discovering "hard to vary" explanations

David Deutsch and his ideas have affected my perception of reality greatly.  He is a brilliant physicist.  His book, The Fabric of Reality, is one of my favorite non-fiction books and does an intriguing job of connecting multiple scientific disciplines into a broader theory.  It even influenced my own fictional book, Odyssey In Black and Blue, which included time travel and free will and where our choices fit in that.  I've got a comic book adaptation that is coming soon, so keep your eyes peeled for that.

I recently watched a TED talk by Deutsch and it is well worth watching.  In it he brings forth a theory about why human progress has seen exponential growth over the last 400 years or so.  Related to the scientific revolution and the Enlightenment, Deutsch makes a subtle argument that the key discovery that humanity has come upon is the ability to distinguish between good and bad explanations of the physical world.  To him, the key distinguishing feature of a good explanation is that it is "hard to vary," whereas bad explanations, such as explanations of seasons varying based on the actions of mythical gods, are "easy to vary" and therefore do not get to the heart of explaining the physical world accurately.  It is a compelling argument, and the TED talk is well worth watching.