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> Part of me even thinks it’s a more straightforward “data science”-problem when you ask the user what they want instead of playing the guessing game with tensors. Instead of worrying about an optimal recommendation, maybe there’s something to be said to allow users to customize instead. But why would bol.com ever consider this? Allowing for customization might be something that users are interested in, but it may cause them to customize for products with lower margins.

Optimizing profits at the expense of everything else is a surprisingly large part of much dysfunction on the internet. Significant parts of the internet are sponsored by ads and this business model creates perverse incentives for the people operating the infrastructure that serves those ads [1]. This is most obvious in social media but it's starting to be the case for Google as well, the quality of their search is continuing to degrade and more of their results are sponsored ads or SEO optimized sites instead of actually useful or pertinent pages [2]. I now mostly look for academic articles when I want to do actual research because most sites matching the keywords I'm looking for almost never contain any semantically relevant content.

1: https://niklasblog.com/?p=25416

2: https://www.washingtonpost.com/news/arts-and-entertainment/w...


We're not actually and assuming that is the case is why we're in the mess we're in right now facing an existential risk from global warming and potential ecological collapse.


Related: https://theanarchistlibrary.org/library/david-graeber-after-.... It's cool to see people waking up and getting organized.


Just a heads up, worksheet 5 has an error: (P ↔ Q) → (R ↔ S) → (P ∧ Q ↔ R ∧ S). That proposition is not actually true.


It’s probably supposed to be (P & R) <-> (Q & S)


Yup, transposition error.


Thanks so much! Fixed.


PS I cannot believe my undergraduate teaching material is on HN! I am a math lecturer and this is just my course notes for my UGs.


It's very fun. Thanks for putting it together.


At the rate things are going large parts of India will become uninhabitable: https://phys.org/news/2021-06-india-climate.html, https://www.dw.com/en/india-climate-change-ipcc/a-58822174. Similar things can be said for many other places that are currently near tipping points in terms of frequency and duration of heat waves and droughts.


Unrelated to the article but I ran across an interesting result recently that is related to AI (and the hype surrounding it): Let A be an agent and let S be a Turing machine deductive system. If A correctly understands S, then A can correctly deduce that S does not have A’s capability for solving halting problems. [1]

One way to interpret this is that all existing AI systems are obviously halting computations simply because they are acyclic dataflow graphs of floating point operations and this fact is both easy to state and to prove in any formal system that can express the logic of contemporary AI models. So no matter how much Ray Kurzweil might hope, we are still very far from the singularity.

1: https://link.springer.com/article/10.1007/s11023-014-9349-3


Your argument is wrong or miscommunicated. The AI itself can figure only some of the halting problem results, not all, plus it can make a mistake. It is not an oracle.

Recursive neural networks are not necessarily halting when executed in arbitrary precision arithmetic.


Have you read the referenced article?


I’ve read a fair portion of it now (at least, a fair portions as far as reading on one’s phone goes), but not all of it yet, and while I do think it seems to probably be making some interesting points, I do feel like it is taking a fair bit of time to get to the point?

Maybe that’s partly due to the expectations of the medium, but I feel like it could be much more concise to, instead of saying, “here is a non-rigorous version of an argument which was previously presented at [other location] (note that while we believe the argument as we are presenting it is essentially the same as it was presented, we are making this different choice of terminology). Now, here is a reason why that argument is insufficiently rigorous, and a way in which that lack of rigor could be used to prove too much. Now, here is a more rigorous valid version of the argument (with various additional side tangents)”, one could instead say “Let objects X,Y,Z satisfy properties P,Q,R. Then, see this argument. Now, to see what this is applicable to the situations that it is meant to represent, [blah].”


Ya, it could be more concise but I think that would require more prerequisites from the reader in terms of model theory and formal logic.


> all existing AI systems are obviously halting computations simply because they are acyclic dataflow graphs

No they aren't. Think about LSTMs for example.


So how do you get a value out of an LSTM?


Run it for as long as you want and look at the output state.

How do you the a value out of a person?


So then in the statement of the theorem the agent A can determine how many cycles the unit will run before halting, correct?


By determine do you mean predict or choose?


I mean by looking at the source code for the neural network someone can give an upper bound on how many steps will be required before the entire network halts and gives an answer and they can prove that their upper bound is really an upper bound.


They need to know the input length too. With an infinite input it will never halt.


Yes, that's the usual assumption when working with Turing machines and proofs. But I guess you could also allow infinite inputs and it wouldn't make that much difference, e.g. computing exp(x) for some real x as input.


Direct link: https://www.city-journal.org/california-switch-to-primarily-...

Really nice analysis of the non-viability of wind and solar:

> Such realities expose the silliness of the oft-repeated claim that solar or wind power have achieved “grid parity,” meaning that they can produce electricity for about the same cost per kilowatt-hour as a conventional machine—when they’re running. To match the energy produced by one conventional machine each year, and for years on end, you need at least two solar/wind machines, plus the batteries. That combination puts the sun/wind/battery option at roughly triple the capital cost of grid-scale conventional power. Even so, the cost for 12 hours of storage at U.S. grid-level alone would be about $1.5 trillion, and that would still leave the nation episodically in the dark. The alternative? A conventional grid with about $100 billion worth of conventional backup/peakers.

The only really sensible option at this point is nuclear and then maybe eventually hydrogen and fusion.


https://calmatters.org/commentary/my-turn/2021/05/will-calif...

It looks like we are going for blackouts here in California.


Ya, it's not looking good.


2 years and still recovering.


The article isn't dismissing conspiracy theories. The article is suggesting that conspiracy theories should be taken seriously and analyzed like religions because most conspiracy theories are very similar to monotheistic religions.


Except that theories rooted in facts, with evidence, and a track record of successful predictions, has nothing to do with mythology.


Do you have an example?


How about the 30 or so that I listed in my original comment above… read much?


Do you have links to long form essays and analysis about why those conspiracy theories were any different from all the other ones? Similarly, what are current conspiracy theories that are more than just conspiracy theories and are backed by actual evidence?


The blik isn't the pizza parlor hiding bad actors in the basement, it's the belief that Hillary Clinton and her friends are the ones orchestrating the operations of the pizza parlor.


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