Richard Feynman: Magnets and Why Questions

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deanCommie · 2024-09 · Reference

The same is true about the terms "waves" and "fields" when it comes to quantum mechanics. They're analogies. The concepts need names, but I think they do more harm than good because people then start with a mental model of a membrane or a surface - something they have experience seeing waves in. And then after 1 or 2 steps where the analogy helps, it breaks down, and people start being confused. Of course the alternative isn't any better. If they had named it a "Wazoo function" and a "Quantum Flarg" everyone would've just kept asking "OK but what IS a Wazoo? What IS a Flarg" and not been satisfied with a "Yeah, it's a fundamental own thing". Feynman, of course, has a pretty definitive response on the difficulty of this problem: [VIDEO]

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acqq · 2019-07 · Reference

> Why is there subjective experience? It evolved in animals because it is advantageous. It is known that even the simplest worms can make a difference between the part of their own body and the body of the other worm or the rest of the environment: they would eat another worm but not their own tail. Worms eating their body are typically not having an advantage (but the local optimums of scarifying a part of the body can of course still develop). So the "subjective experience" of distinguishing between "me" and "anything else" allows the living things to protect themselves from the rest of the environment. Then if you question "why are there living things" the answer is again that they evolved exactly because the property of these units "preserving" themselves and duplicating that behavior -- these entities which don't have such properties remain lifeless and don't reproduce. In short, a "subjective experience" is still a "simple" emerging property of the complex enough living organisms. I intentionally quote "simple" as for us it is "of course" not simple, even if it can be reduced to such a simple explanation. The reason for that is again known today: the existence of life as we know it today is a result of the 14 billion years of the development of the environment during which effectively each moment and every detail happening just a bit different could have resulted in what we know as our environment not existing in this very form we know today and therefore "we" as we und

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tedsanders · 2015-12 · Reference

This is not a consensus view by macroeconomists. While fraud may have been important, and possibly more important than macroeconomists believe, I think you do a disservice to the HN reading community by not acknowledging the vast body of experts who have already tried to answer the question of what caused the Great Recession. It's a very difficult question to answer convincingly, given that we cannot run multiple trials to see any counterfactual scenarios. I think any attempt at an answer should be presented with humility and caution and nuance. Wikipedia discusses a bunch of factors related to the Great Recession, correctly mentioning that different economists place different weight on them: [LINK] Here's a video by Tyler Cowen that discussions the Great Recession in terms of four DIFFERENT macroeconomic models: [LINK] Lastly, I'll say that even talking about causation generally is difficult. If someone buys a gun and shoots me, what was the cause of me getting shot? If guns had been outlawed, I wouldn't have been shot. Is it Congress's fault? If the shooter hadn't pulled the trigger, I wouldn't have been shot. Is it the shooter's fault? If I hadn't failed to jump out of the way, I wouldn't have been shot. Is it my fault? Defining causality when there are many serially dependent steps is not easy. So when someone asks, why did the Great Recession happen, it's hard to even know what the question means. Feynman has a famous interview segment where he talks about the difficulty

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