Socrates’s “all I know is that I know nothing” and “know thyself” more and more reveal to me something new about life, philosophy, and the nature of being.
Ask HN: Concepts that clicked only years after you first encountered them?
601–610 of 946 posts
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#602Earlier quoted context omitted.
This was in django, where a good such test would set up the database, call the function, then check that the new state in the database is as expected. (Which IIRC is what I changed it to)
I've seen tests like that ("has the mock been called")... and in general I've felt that they were kinda useless. Thinking about the original TDD approach -- red, green, repeat maybe it's not that bad? I prefer your approach, where you actually verify the state change. But in the absence of that, I wouldn't mind the "call the mock" approach. At least it does change some of the contract?
I would say it's worse than no test, because it discourages refactoring. Any alterations would make the test fail, even if it still does what it's supposed to do.
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#603Earlier quoted context omitted.
I often see Harari and Graeber's being discussed at the same time, and I am always surprised. Harari write pop sci, a grand narrative with many liberties with both history and science. Graeber's books are heavily referenced pieces of work. Debt: The first 5000 years ends at 73% on my Kindle, because the remaining 27% of the book (144/534 pages) is references and footnotes. Their books are not in the same intellectual…
The number of references are not an indication of the quality of a work. Adam Smith wrote a whole book on The Theory of Moral Sentiments but in Debt , Graeber invents Adam Smith's morality whole cloth. I have no intention of reading Dawn of Everything but reviewers have noticed references that say the opposite of what the authors claim they say.
I am aware that there are problems with the books, even some serious ones. But I find that hardly surprising from a book that references a 1000 other scholarly works. But the reason you can critique the book effectively is because he references where his claims originate from.
In the language of this essay [1], Graeber's work is legible, Harari's not at all.
[1] https://acesounderglass.com/2022/02/07/epistemic-legibility/
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#604Earlier quoted context omitted.
This is what made it click for me, can recommend it: 3Blue1Brown -- But what is the Fourier Transform? A visual introduction. https://www.youtube.com/watch?v=spUNpyF58BY
That video did the same for me. I also like the reducible video for Fast Fourier Transforms as well as the Veratasium piece that shares some fun history. Reducible - FFTs the most ingenious algorithm ever https://youtu.be/h7apO7q16V0 Veritasium - The Most Important Algorithm of All Time https://youtu.be/nmgFG7PUHfo
100%,those are excellent, but didn't exist when it first clicked for me. Being in university now must be great having such access to explanations that really get to the root of a concept
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#605The fourier transform. Encountered it first in my undergrad engineering degree, it was presented as dry mathematics, with no real explanation, just threw complex exponentials at us, and pages of derivations. Years later I actually use it in my job, and through that and other material can see its beauty, and how its actually not that complicated. Some great resources like this helped a lot: [0] https://betterexplained…
In case you didn't already know; Who Is Fourier?: A Mathematical Adventure is an excellent illustrated book on this.
Thanks, I'll look it up!
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#606Earlier quoted context omitted.
If I lived in a majority-Cholita area, I would not give it a second thought. If I lived in an area with not many Cholitas, I would wonder if there was a reason the group had only Cholitas.
Really? I live in Japan but am not Japanese. I speak Japanese and have many Japanese friends. I’d feel quite different about joining a hiking group that was 100% Japanese as opposed to one that had a mix of Japanese and non-Japanese people.
Seems likely there's a Japan/US difference here
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#607Narcissism. My grandmother was a terrible narcissist. I loved her dearly and she had a lot of wonderful qualities, but The quality that stood out the most, sadly, was narcissism. My mother was also a narcissist to a somewhat lesser degree. It didn't occur to me that I too was a narcissist until I was about 35 years old. It took waking up in the corner of the living room in my friends one bedroom apartment Early one m…
I find it interesting when people come from a long family line of narcissists (not uncommon) that they often attribute it to a cycle of being raised by a narcissist making you into a narcissist. it seems more likely that there is a genetic/biological basis for this personality trait
It’s possible but I don’t really buy it. There’s a very real sense in which narcissism is just a lack of acquired skills that most people have. That skill being the ability to see both the good things and the bad things about yourself and about others at the same time. If you’re raised in an environment where your caretaker teaches you they are always right (with severe consequences for pointing out they aren’t) then it is hard to develop a nuanced worldview. The child can either get on board with the parent, become “one of the good ones” and become a narcissist themselves or they can become a black sheep of the family, usually with worse outcomes.
Importantly, the skills can be learned as an adult it’s just hard to do. I come from a long lineage of family members who did not know how to swim, but I don’t think that there’s a genetic basis for this.
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#608Special Relativity. E.g. how could it be that observers A and B (moving relatively to each other) both think that time passes more slowly for the other one? How is that not a contradiction?
Man, that took me a while. The solution: A and B have different notions of simultaneity and won't agree on which events occur at the same time. In particular, they won't agree on time measurements.
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#609Earlier quoted context omitted.
I've always had a hard time because I was thinking.. why would I carry the performance hit of instantiating objects for a bunch of stuff?
Could be wrong but, at least in C++, there's realistically no overhead to creating a trivial object that you wouldn't have by manually instantiating the variables anyway. (Ignoring virtual stuff, lengthy constructors -- code run is code run but a raw object I think is by itself relatively harmless.)
you are right - in c++ (and in most other languages that support oo) there is no overhead on instantiating a structure, or variables, that you would not have to pay anyhow.
Re: Ask HN: Concepts that clicked only years after you first encountered them?
#610Docker.