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Reality has a surprising amount of detail (2017)

johnsalvatier.org

31–40 of 304 posts

Re: Reality has a surprising amount of detail (2017)

#31
post #13

Super interesting! I feel like most programmers have it easy. For the most part the first step of a program is "take the universe and project it to some fixed structure". The entire universe of complexity gone. The box has to be the right shape, but even if it's not things can mostly work. You forget to account for wind and suddenly your New York skyscraper is falling over. Forget a field in your database and you jus…

In light of some memorable software design failures (which includes not just code but UX design, usage scenarios, compliance etc) I would kindly disagree. And the people of Hawaii would too I am sure.

It really depends what the software is used for. Software is just peoples thoughts and intentions codified for quick access/evaluation.

If they are used for a game it might not be important, if they are used for something important it also becomes important and exactly because the complexity of real life is difficult to account for ahead of time.

Re: Reality has a surprising amount of detail (2017)

#32
post #13

Super interesting! I feel like most programmers have it easy. For the most part the first step of a program is "take the universe and project it to some fixed structure". The entire universe of complexity gone. The box has to be the right shape, but even if it's not things can mostly work. You forget to account for wind and suddenly your New York skyscraper is falling over. Forget a field in your database and you jus…

In light of some memorable software design failures (which includes not just code but UX design, usage scenarios, compliance etc) I would kindly disagree. And the people of Hawaii would too I am sure. It really depends what the software is used for. Software is just peoples thoughts and intentions codified for quick access/evaluation. If they are used for a game it might not be important, if they are used for somethi…

Sorry, I didn't mean to minimize the consequences.

There are massive failures, and now, more than ever, software interacts with other software in unpredictable ways.

I was just expressing the feeling that things are even worse in other domains. Though sometimes automating a huge unstructured mess is difficult, imagine having a huge unstructured mess and dealing with it by hand!

Programmers might have many problems, but at least a subset of the work happens in a purely mathematical space.

Re: Reality has a surprising amount of detail (2017)

#33

Something I've noticed now that we're all communicating online in written form: a lack of people saying "I don't know" It seems that everybody knows everything. Whatever the issue, a little bit of Googling and suddenly you know all there is to know. Even more wondrous, no matter what position you take on anything, some more search engine Kung Fu and you can find a hundred people willing to support you with arguments,…

Maybe it's just an impression based on the fact that people who do not know do not care to write it. I don't know :)

Yes, and also consider the relationship between knowing an answer, being confident in your knowledge, and having the time to explain details or find sources.

People (who are intellectually honest) say "I don't know" when a question is specifically addressed to them, and so they feel a responsibility to give an answer. They don't respond at all when they don't know the answer and they haven't been addressed... except if they are motivated by curiosity and wish to indicate that they, too, are interested in the answer.

Incidentally, the mistake of assuming that everything on the Net is addressed to you is a common failing among people who have little experience. It happens on Facebook all the time...

Re: Reality has a surprising amount of detail (2017)

#34

Having never done any carpentry nor googled the answer, the first thing that's coming to mind is to place the board at the angle you want, then use a straight edge (like a level) extended out from the floor of the upper story to trace a line on the board. Cut the board, then flip it over so that cut side is on the bottom, and then repeat the process to cut the top. Edit: I guess my first line will read as a disclaime…

I think you've got a slight problem with this approach, that a diagram should illustrate if you draw the board as a rectangle and not a line. Thought experiment time:

Let us assume that you rest the board in such a manner that the angle between the edge of the board and the vertical wall is 45 degrees. The edge of the board is tangential to the corner of the wall and the upper floor, and you scribe the horizontal line, then cut it.

When you now flip the board around so that the cut you made will rest flush against the ground, the other end will still be a line that's tangential to the 90-degree join between wall and upper floor; it won't be flush against the wall.

For a 45 degree angle, you could go "oh, I'll just scribe a vertical line upwards where the board is tangential to the corner, and cut it." When you do this, you'll find the board may be flush to the ground, but it extends past the first floor, because you basically cut it too long. You could, by careful repeated cutting, shave off enough from the bottom to get it to fit flush to the floor, and flush to the wall... but that's a lot of cutting.

Now, you could apply some simple (?) maths here, and realise that for a 45 degree angle, the answer is that the board has to be some multiple of square_root(2) long, but that's maths, and that's not allowed. :)

Back to the physical approach. What if we did that horizontal cut, then rotated the board so that it became a vertical cut? Well, now it should be flush against the wall, but the end on the ground is resting on the corner of the board, not a face. You could cut it so that the "back" (furthest from the wall) corner was flush to the ground, but now the top of the board will be a few inches lower than the upper story.

This is non-trivial :) It gets worse if you're not using a 45 degree angle which makes things symmetrical.

Re: Reality has a surprising amount of detail (2017)

#35

There's something of a connection here to Zen and the Art of Motorcycle Maintenance. Two examples come to mind: 1. The narrator thinks it's important to have in your toolset hammers of multiple hardness, because your hammer should be softer than whatever material you're hammering on at the time. At least, that's how I remember it; I might well be wrong about -- well, about the DETAILS of that example. Please correct…

He’d been innovating extensively. He’d been having trouble with students who had nothing to say. At first he thought it was laziness but later it became apparent that it wasn’t. They just couldn’t think of anything to say.

One of them, a girl with strong-lensed glasses, wanted to write a five-hundred-word essay about the United States. He was used to the sinking feeling that comes from statements like this, and suggested without disparagement that she narrow it down to just Bozeman.

...

It just stumped him. Now he couldn’t think of anything to say. A silence occurred, and then a peculiar answer: “Narrow it down to the main street of Bozeman.” It was a stroke of insight.

...

He was furious. “You’re not looking!” he said. A memory came back of his own dismissal from the University for having too much to say. For every fact there is an infinity of hypotheses. The more you look the more you see. She really wasn’t looking and yet somehow didn’t understand this.

He told her angrily, “Narrow it down to the front of one building on the main street of Bozeman. The Opera House. Start with the upper left-hand brick.”

Her eyes, behind the thick-lensed glasses, opened wide. She came in the next class with a puzzled look and handed him a five-thousand-word essay on the front of the Opera House on the main street of Bozeman, Montana. “I sat in the hamburger stand across the street,” she said, “and started writing about the first brick, and the second brick, and then by the third brick it all started to come and I couldn’t stop. They thought I was crazy, and they kept kidding me, but here it all is. I don’t understand it.”

Neither did he, but on long walks through the streets of town he thought about it and concluded she was evidently stopped with the same kind of blockage that had paralyzed him on his first day of teaching. She was blocked because she was trying to repeat, in her writing, things she had already heard, just as on the first day he had tried to repeat things he had already decided to say. She couldn’t think of anything to write about Bozeman because she couldn’t recall anything she had heard worth repeating. She was strangely unaware that she could look and see freshly for herself, as she wrote, without primary regard for what had been said before. The narrowing down to one brick destroyed the blockage because it was so obvious she had to do some original and direct seeing.

He experimented further. In one class he had everyone write all hour about the back of his thumb. Everyone gave him funny looks at the beginning of the hour, but everyone did it, and there wasn’t a single complaint about “nothing to say.”

In another class he changed the subject from the thumb to a coin, and got a full hour’s writing from every student. In other classes it was the same. Some asked, “Do you have to write about both sides?” Once they got into the idea of seeing directly for themselves they also saw there was no limit to the amount they could say. It was a confidence-building assignment too, because what they wrote, even though seemingly trivial, was nevertheless their own thing, not a mimicking of someone else’s. Classes where he used that coin exercise were always less balky and more interested.

As a result of his experiments he concluded that imitation was a real evil that had to be broken before real rhetoric teaching could begin. This imitation seemed to be an external compulsion. Little children didn’t have it. It seemed to come later on, possibly as a result of school itself.

-- Robert Pirsig

Re: Reality has a surprising amount of detail (2017)

#36

Nice story (the first one) about the "top-down" approach, where you discover new complexity and choices at every level. Note how the discovery of new detail ends when you choose to use existing building blocks with known properties, based on experience (e.g. screws instead of examining which of the many possible ways of attaching parts would be most suitable). How simple this would be if you could buy pre-cut boards…

When it comes to my day job building software I choose opinionated languages and libraries because they limit the choices I have to make which makes me more productive.

But when I'm playing around in my off time I employee alternative ways of doing things with unusual or niche languages so I can explore details in more depth.

Re: Reality has a surprising amount of detail (2017)

#37
Related:

> Baader-Meinhof is the phenomenon where one stumbles upon some obscure piece of information—often an unfamiliar word or name—and soon afterwards encounters the same subject again, often repeatedly.

It was there all the time, you just didn't noticd it.

Re: Reality has a surprising amount of detail (2017)

#38

Having never done any carpentry nor googled the answer, the first thing that's coming to mind is to place the board at the angle you want, then use a straight edge (like a level) extended out from the floor of the upper story to trace a line on the board. Cut the board, then flip it over so that cut side is on the bottom, and then repeat the process to cut the top. Edit: I guess my first line will read as a disclaime…

I think you've got a slight problem with this approach, that a diagram should illustrate if you draw the board as a rectangle and not a line. Thought experiment time: Let us assume that you rest the board in such a manner that the angle between the edge of the board and the vertical wall is 45 degrees. The edge of the board is tangential to the corner of the wall and the upper floor, and you scribe the horizontal lin…

Further thinking.. instead of scribing a horizontal line, scribe a vertical one at the top, cut that. Then scribe a horizontal line from the back corner towards the wall, cut that. Should then fit flush to both ground and wall.

I should go find a bit of paper and scissors and try.

Re: Reality has a surprising amount of detail (2017)

#39

Something I've noticed now that we're all communicating online in written form: a lack of people saying "I don't know" It seems that everybody knows everything. Whatever the issue, a little bit of Googling and suddenly you know all there is to know. Even more wondrous, no matter what position you take on anything, some more search engine Kung Fu and you can find a hundred people willing to support you with arguments,…

Why would I jump into a thread, on any site, just to say I don't know? There are thousands of threads just on HN that I just let scroll by without participating because I don't know enough to add to the discussion. Explicitly calling out my lack of knowledge on every thread would serve no purpose to anybody.

Online written communications will never follow the same patterns as direct communication, and that is a good thing.

Re: Reality has a surprising amount of detail (2017)

#40

Having never done any carpentry nor googled the answer, the first thing that's coming to mind is to place the board at the angle you want, then use a straight edge (like a level) extended out from the floor of the upper story to trace a line on the board. Cut the board, then flip it over so that cut side is on the bottom, and then repeat the process to cut the top. Edit: I guess my first line will read as a disclaime…

That only works for 45 degree angles. The reason is left as an exercise to the reader.
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