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Comment · 1 year ago
Comment · 1 year ago
Agreed, Friston's Bona Fides are impressive. (Aside: His fame in neuroscience comes from him having written important FMRI software that everybody cites.)

That's also why I worked with his team and read a lot of his papers for a while. His principal idea was originally that neurons perform free energy minimisation. This idea makes a lot of sense, once you understand what free energy means. But, to the best of my knowledge, it has not at all been empirically verified for neurons (I'd be delighted to be proven wrong in this belief). So he went the route of generalising the free energy principle: "the free energy principle asserts that any “thing” that attains a nonequilibrium steady state can be construed as performing an elemental sort of Bayesian inference". Terms "can be construed" and "elemental sort of Bayesian inference" do a lot of work here. Updating and generalising one's research hypothesis is legitimate (albeit one could be more explicit about this), but it weakens the claim being made. Anyway, under a charitable interpretation of those terms, I agree that this is true, but, at the same time doesn't say much. Indeed, under the charitable interpretation it basically equates doing free energy minimisation with existence. Friston has lately said that the FEP is not falsifiable. Take it from the horse's mouth (i.e. a Verses employee): "the free energy principle just applies to stones, it applies to birds, it applies to any kinds of animals" on Machine Learning Street Talk [1].

Here is my current position: from a mathematical principle this general one cannot derive scalable ML algorithms!

> he seems to have joined only in 2022, they were 4 years old at the time.

The company founders have a cryptocurrency and (later) metaverse background.

[1] https://www.youtube.com/watch?v=qxEfcrmTWO4

Comment · 1 year ago
Comment · 1 year ago
Comment · 2 years ago
Geoff Hinton was denied an academic position at the University of Sussex's CS department where he had done postdoc work (That department is now 'famous' for consciousness studies and integrated information theory https://osf.io/preprints/psyarxiv/zsr78. I bet they are kicking themselves now ...)

> "Academia will one day wake up, and realize that"

Charlie Munger famously said, "Show me the incentive and I'll show you the outcome" ...

Comment · 6 years ago

   expertise either mad or catatonic.
Yes.

Unfortunately it still works really well with students, who are not yet knowledgable enough to be able to recognise the Fristonian ideas for what they are--hot air--and who waste their time with active learning before realising that it's currently mostly hot air. I've seen this play out several times by now with my (current and former) students.

Comment · 6 years ago
Regarding average: which average in the sense of: average over what time window? Any specific choice here needs to be justified as happening in the brain.

Regarding "we will find brain models with observable activity that follows the FEP?": abstractly you are saying that your prediction for theory T is that we will eventually confirm T. This does not exclude anything, I can state this for any theory T whatsoever. (For fun, try to instantiate T with outlandish theories, e.g. with "We will eventually find weapons of mass destruction in Irak", or with plausible theories that have failed so far, e.g. "We will eventuallly see supersymmetry". Does your prediction rule anything out?)

Regarding variational Bayes, that was not invented by the Free Energy millieu.

Comment · 6 years ago
Comment · 6 years ago
I have explicitly stated that I am using a simplistic interpretation.

I am neither seeing that Friston has (A) produced anything even remotely resembling a testable framework this "kind of surprise that is being minimized in the free-energy framework" and (B) pointed to any plausible mechanisms in the brain that should that this is in fact "the kind of surprise that is being minimized". He just handwaves.

What clearcut evidence can you give me that humans minimise this "kind of surprise"? What evidence would you accept as falsifying this? Where does Friston make clear that "secondary motivations" don't count? Also making a super vague, unquantified statement like "large contingent of people who are desperately trying to enact conservatism ..." in defense of Friston / free-energy doesn't give me a lot of confidence in the social milieu that this theory comes from. All the more so, since my OPs explicitly criticised Friston for vagueness.

Comment · 6 years ago
Thanks.

I looked at that link but could not find the code that lets me reproduce the results in the paper. Maybe I didn't look hard enough?

Comment · 6 years ago
I cannot see the "these routines [being] available in the development version of the next SPM release". The development version is a 111 MB zip file [1]. When I uncompress the file I get a big flat directory with 100s of files. Which of those is is the software used in the paper? I have a bad feeling about this. I don't see how the authors are displaying intellectual integrity by not releasing, concurrently with the paper, software for such an important problem public health issue.

   ideas are hardly vague. 
   Hard to understand 
The core intuition is easy to understand: brain predicts its observations including observations about itself (proprioception) and acts in a way to minimise surprise. This can be seen as a form of self-supervised learning in the terminology of contemporary machine learning. Lots of people have said somewhat similar things before at a similar level of vagueness. Nobody disagrees that "somehow" the brain learns about the world by prediction and interaction. The interesting question is to go beyond this vagueness: what exactly is the brain doing? Where exactly is the brain minimising 'free energy'? Can I have a testable prediction please?

If read literally, Friston's core intuition is false: people regularly and deliberately expose themselves to surprise, e.g. gambling, watching sports, speed dating. Now there are various ad-hoc fixes to save free-energy-minimisation, which should make the theory more testable, but Friston then has to state clearly which of the many conflicting ad-hoc fixes are in place, and explain how they manifest themselves in the brain! Friston has been confronted with those problems many times, but he basically ignores them.

[1] https://www.fil.ion.ucl.ac.uk/spm/covid-19/#software

Comment · 6 years ago
Comment · 6 years ago
Thanks!

The C FFI worries me because if I choose Rust for our project I'll need to interface a huge number of C / C++ libraries with the Rust core. OTOH, Mozilla seems to be doing fine mixing Rust with C++.

Comment · 6 years ago
7

3+4

2nd-smallest double Mersenne prime

Number of continents

Comment · 6 years ago

   has _a lot_ of issues 
I value your perspective on programming languages. Would you mind sharing those issues? I am in a position where I can and do influence PL design.

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