Ep 111: Probability - Reality, Rationality and Risk

"Slides" are referred to in this episode. Their absence will not hinder understanding for audio-only listeners - enjoy!

This is a "talk about a talk". Back in 2015 David Deutsch gave a lecture titled "Physics without Probability" which ranged over the history of probability, it's uses and misuses and essentially concluded there was no way in which probability featured in the real world - according to known physics. This is a shocking (for most) conclusion and something many will baulk at. The original talk can be found here: https://www.youtube.com/watch?v=wfzSE... and I strongly commend it to all listeners/viewers. Over the years since I have found myself over and again referring to this talk and pointing others to it on the topics of quantum theory or Bayesianism or simply risk assessment.

I do not understand why that talk does not have 10 times the number of viewings. Or 100. It is ground breaking, useful, compelling stuff. It is neither too technical nor too subtle. So this is my attempt to re-sell that talk and provide a slightly different phrasing of what I think is a clear articulation of those important ideas.

People claim to think in terms of probabilities. Physicists speak in terms of probabilities. Philosophers and those who endorse Bayesianism speak in terms of probabilities. How can we do away with it? As an instrument probability might work well. But then so can assuming that your local land is flat even though we know that - strictly - the Earth is curved. Does this matter? If you care about reality and explaining it and hence genuine rationality then you should. Especially when it comes to risk assessment. Towards the end of the podcast I go beyond David's talk into my own musings about various topics - including the notion of risk which has been a request on ToKCast. As always errors herein are my own. If you enjoy this podcast, consider supporting me on Patreon or Paypal. The links for donating can be found on the landing page right here: https://www.bretthall.org