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Reality has a surprising amount of detail (2017)

johnsalvatier.org

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

#81

Post by natureiskino »

didgetmaster wrote: post #35

I think we have all written some code that looks bulletproof to us. We run a set of tests with all the inputs we can think of, and it passes with flying colors (after several iterations of course). Then we give it to someone else and it fails on their first or second attempt. They simply tried to use it in a way that we did not anticipate. It doesn't mean that we are dumb for not thinking of those possibilities; it j…

>that looks bulletproof to us

And it pretty much is most times. For us. But indeed I did run into the "why would they use it like that though" scenario, where it fails. So I have to patch that usecase. At which point I go all "ok now it's really done" until another fringe usecase pops up and so on and so forth. And I did think about how sure I was it was bulletproof, humbling moment.

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

#82

Post by esikich »

WastedCucumber wrote: post #7

The first time I built a freestanding bookshelf, I put a lot of effort into making the feet level and the back straight and at a right angle to the feet. Once I put it up against the wall I'd built it for, I realized I'd solved completely different problem than the problem I really had. I needed crooked bookshelf, since the wall was totally tilted. In the end I screwed some wall shelves in and called it good enough.

"Never trust the carpenter"

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

#83

Post by atoav »

mapcars wrote: post #20

Reality does not have amount of details, it is infinite in all directions. Its only that we perceived certain amount of details, some more some less. One can spend their whole life mastering a single aspect and there always will be room to improve.

The statement refers to human perception of reality.

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

#84

Post by boomskats »

dcrazy wrote: post #72
fhe wrote: post #62

Earlier quoted context omitted.

I want to thank you for the following reasons: - that's an amazing, mind-opening essay; - I've been looking for this toy (Meccano) for my entire adult life. I remember playing with a set that my mom got me when I was a kid, but I didn't know what it was called, and neither did my mom. And when I describe it to people, everyone kept telling me it was Lego (Lego is a much better-known toy brand in this part of the worl…

In the U.S., Meccano is known as Erector.

I'm amazed it's not more popular with a name like that!

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

#85

Post by MASNeo »

With the complexity of the systems we build it’s humbling and refreshing at the same time to read this. Indeed we are quick to default to what we know. Yet the answer may lie well outside of our expertise. I often build things many consider impossible and find that exactly the attention to detail and seeking contrarian views has helped avoid the worst mistakes.

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

#86

Post by internet_points »

mcswell wrote: post #50

One thing he didn't mention is getting the first and last steps to be the same vertical distance as the others. Nothing will trip you up (literally!) so easily as a final step that is a different height than the other steps. I thought of this because this morning I was putting a small fence around some plants we want to protect from deer. The fence consisted of 20 sections (bought on Amazon), each about 24 inches wid…

Now I'm trying to imagine a staircase with a non-integer number of steps

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

#88

Post by mjmas »

atoav wrote: post #59
WastedCucumber wrote: post #7

The first time I built a freestanding bookshelf, I put a lot of effort into making the feet level and the back straight and at a right angle to the feet. Once I put it up against the wall I'd built it for, I realized I'd solved completely different problem than the problem I really had. I needed crooked bookshelf, since the wall was totally tilted. In the end I screwed some wall shelves in and called it good enough.

When I worked as a camera guy on film sets, this was a typical occurrence. You level out the camera trypod with the magic eye on the tripod. The magic eye being a small amount of liquid with a single bubble inside, pointing always upward. Soon you realize that an surprising amount of walls are just not straight or level.

aka spirit level?

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

#89

Post by vintagedave »

dwd wrote: post #55
smokefoot wrote: post #49

Earlier quoted context omitted.

Woodworking taught me a lot about planning and design. As a young person, I was like the authors brother. I just wanted to do the thing, not draw a diagram and figure out how much wood I need, or build a fixture to mark the stair lines. Woodworking (the more constructive, furniture-making kind), rewards a deliberate, controlled process and it savagely penalizes mistakes. Those lessons transfer well to other disciplin…

Absolutely. Woodworking was part of my first 3 years of high school, but it was mainly about learning safety and tool usage and not planning, estimating, selecting or purchasing timber. These days I only want to go to the lumberyard once for a project. Learnt the hard way on my first project that you need to take the time to carefully select the timber - checking straightness, matching grain and also colour before I…

That's also a lesson about what people will sell you. First time I went to a lumberyard, I was (coincidentally) with a friend who did a lot of woodwork. I thought, well, I've just paid for a pack of wood, I'll get it. The worker there was completely happy with that. My friend stopped me, and inspected each piece.

Sure enough, several had cracks at the ends, knots in poor places, and other things that, had I bought it, would have caused me trouble.

I can be a naive person in that I assume good faith. I would never knowingly sell something poor quality to someone else. I had assumed because I was being sold it, it was okay.

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

#90

Post by 21asdffdsa12 »

kQq9oHeAz6wLLS wrote: post #63
xeonmc wrote: post #57

Earlier quoted context omitted.

I wonder if this could all be solved if doors are triangles instead of quadrilaterals.

Or round, like the hobbits do

You lough, but the cork always plugs the bottle eventually. Cone shaped round doors with cork on the rim.
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