21. Chaos and Reductionism
Why Hacker News recommends it
Pointed to as a clear statement of irreducible complexity, the limits of reductionism, and why simple neuron-level explanations fall short.
What it is
Robert Sapolsky's Stanford lecture on chaos and reductionism, which he calls one of the hardest of the course. It examines the limits of breaking systems into parts to understand them and introduces chaotic systems.
Recommended by 1 HN commenters across 1 different months, 2017 to 2024.
What Hacker News said
Recommends animal_spirits · 2020-10 · on “Washington crews destroy first U.S. “murder hornet” nest”
I think its a good start to learn about chaotic systems instead. For most systems, minute parameter changes can have dramatic effects on the predictability of the system [this video]
Cites lr4444lr · 2017-06 · on “It’s Complicated: Unraveling the mystery of why people act as they do”
Maybe, but assuming Shermer has correctly conveyed the contents of this part of the book, Sapolsky's got a lot of nerve asserting so confidently in this book that there is such a definitively deterministic core to humans behavior at the macro level while acknowledging irreducible complexity irrespective of scale as he did so clearly in one of his Stanford lectures: [this video] . I really like the guy as an educator, and I'm sure he's earned his scientific chops, but that doesn't qualify him to be even an amateur ethicist.
Cites IIAOPSW · 2022-08 · on “MIT scientists discover neurons that light up whenever we see images of food”
Actually the opposite. The story of a single neuron on/off state for everything we experience is just that, a story. If you tried to build a skull large enough to hold all that, it would burst. The reality is that paradigm of hardwired neurons works well for the initial layers of processing (Eg recognizing lines and circles in visual stimuli), but that same model can't be repeated all the way up to the point of having a "grandmother neuron" for recognizing Grandmas face. There's just too many possible states of grandmas. There has been some evidence (like this study) that maybe sometimes there are "sparsely coding neurons" (Eg, some monkeys apparently have a brain cell that reliably responds
Cites IIAOPSW · 2023-03 · on “Evidence of a predictive coding hierarchy in the human brain listening to speech”
This is simply impossible. The premise that the brain is a big lookup table is appealing, and that sort of 1 neuron = 1 represented item concept certainly happens at the initial stages of the sensory pipeline, but if you attempt to scale it up and up to higher levels of abstraction, to the point where you have neurons that have rote memorized every orientation of your grandmothers face (and everyone else's face), you would need to have far more neurons than can possibly fit in any animals head, let alone yours. This concept is literally known as a "grandmother neuron", and its widely considered to be debunked. I refer you to this neuroscience lecture. [this video] Beyond the simplest, most common
Cites nyrikki · 2024-10 · on “Critique of Freakonomics interview with psychologist Ellen Langer”
Nit: It goes a bit deeper than that. Note this talk by another Pop Sci personality Robert Sapolsky, where he talks about the limitations of western reductionism. [this video] Yet his latest book on free will exclusively depended on an reductionist viewpoint. While I don't know his motivations for those changes, the fact that the paper he mentioned was so extremely unpopular that I was only one of a handful that read it surely provided some incentive: > "REDUCTIONISM AND VARIABILITY IN DATA: A META-ANALYSIS ROBERT SAPOLSKY and STEVEN BALT" Or you can go back to math and look at the Brouwer–Hilbert controversy, which was purely about if we should, universally, accept PEM a priori, which Church, Pos