Textbook Group meeting for Parr, Pezzulo, Friston 2022 .

Hello everyone, it is June 16th, 2022, and it's meeting 7 of the Active Textbook Group, Cohort 1. We're in our second discussion of Chapter 3. Today we'll be looking at the questions that haven't been addressed, so the ones without thumbs, and also it's not too late to add more questions or to upvote questions. And then additionally, since the Math Learning Group has been quite active in providing synchronous affordances for conversation around some of the background on the math, as well as some aspects of the equations that we'll go through today, and also even to applications of the math and developing notebooks and such, we'll take a look at the math in our move through Chapter 3. Before we go to the questions, does anyone have anything that they just want to remark on Chapter 3? Ali, and then anyone else? Yeah, well, last week I talked about how I changed my mind about these bottom-up and top-down characterizations of low road and high road respectively after reading Chapter 3, but it turns out that they are in fact bottom-up and top-down approaches after all. You see, I came across this, in my opinion, undeservedly lesser-known piece of beautiful, beautiful writing by Carl Fristen, which explicitly argues for such characterizations and the philosophical importance of this distinction. It's called Beyond the Desert Landscape, and it's inconspicuously hidden in this book, Andy Clark and his critics. So, I'd like to quote a couple of sentences from this writing. Well, he writes, quote, The high road stands in for a top-down approach that starts by asking fundamental questions about the necessary properties things must possess if they exist. Using mathematical variational principles, one can then show that existence is an embodied exchange of a creature with its environment. That necessarily entails predictive processing as one aspect of a self-evidencing mechanics. The low road is the purpose the agenda established by, is to pursue the agenda established by Kant and Helholzson generalize in a bottom-up way the capacity for inference and prediction to see how far it takes us in understanding embodied exchange with the environment. So, if anyone likes to gain a deeper understanding about these conceptual characterizations, I highly, highly recommend this chapter of this book and quite unusually for Fristen writing. It also lacks any mathematical formalism. It doesn't include a single mathematical equation there. Thank you. Yeah, in a recent stream we also talked about the desert landscape and Clark's concern was that we might do away with what populates our implicitly assumed to be rich ecosystems of psychology, philosophy, and so on with important ecosystem players like goals. And so, the fear or concern was that we might be in a Quinean desert landscape if we replace some of these, again, implicitly or explicitly stated to be rich constructs like goals and we're like, well, it's just distribution matching. If we're not just a certain way, then we've made some sort of like a desert monoculture and that would be depauperate of what? What does Clark say to his desert living critics? All right. If anyone else has a thought, they can raise their hand. Otherwise, we can look at the questions. Okay. So, this first question. If one defines preferred states as expected states, one can say living organisms must minimize the surprise of their sensory observations. I'm not clear on the ontology here. Is it that preference is the same as expectation or that formally we can use them in the same equation? Is that an ontological claim? And is the free energy and physics an analogy or an ontological assertion about how things really are? So, one starting place was, I found the slide and so I wanted to highlight it. This was in Free Energy, a user's guide, which was live stream number 37. The slides will be probably a little bigger. It's worth restating just how unusual it is to interpret P as a measure of both probabilities and preferences.…