Comment by Timothee | Hacker News Reader

Comment by Timothee | Hacker News Reader

This is part of the things that I list under "human-built things I technically understand (more or less) but are still completely baffling if I stop and think about it".

Amongst these:

- same example with Google Instant: the fact that what I type goes to Google and back that fast and that I never get somebody else's page is pretty amazing;

- CRT monitors: a flow of electrons is bent with electric current to hit a specific point on the screen, for millions of dots at least 30 times a second and it never misses its targets; (leaving aside that we were able to get a constant flow of electrons in the first place…)

- car engine: fuel is injected, compressed, lit up in cylinders at 3000rpm to make a 4,000 vehicle move at 65mph and the engine barely ever have hiccups.

- cell phones: I'm driving in California and can talk to my Dad who is in a high-speed train in France. It works and you can't even notice a significant delay.

And there are obviously so many more things like these…

It's like this Louis C.K. bit about people who complain about being stranded 40 minutes on the ground before taking part of "the miracle of flight". We should spend more time amazed at when it works than pissed at when it doesn't.

I think that's a red herring.

I mean, isn't that just the marvel of abstraction? I can show you how it works, on a basic level: See, it goes around like this. This connects here. That switch opens. This moves back, and that's the behavior that we're looking for. Easy.

Why is it that when that same thing happens a hundred times a second, the emergent behavior suddenly becomes mind-boggling? It's just the same thing, faster. You already understand it. Your brain cant work fast enough to see what's going on, but thats exactly why we built the machines: to translate very fast things into things slow enough to understand. The complexity of the speed is illusory.

It strikes me as like a small child, watching the cars go by-- Zoom! Zoom! Surely that is the most amazing thing that exists. But when she grows up, she learns that everything has a velocity, which has to be some number, so it might as well be high. The interesting things are still interesting, moreso even, when it's going very slow. Just going fast is kind of boring.

What's cool are the things that emerge when you abstract. You have a car, and you know why that works. The connection between gasoline and forward motion is straightforward enough. But as soon as you have three cars on a road, you have traffic, and that's something fundamentally new. And you can analyze the traffic, figure out how it works-- but can you see how traffic is fundamentally dependent on the behavior of gasoline? And gasoline on the behavior of a refinery?

And what happens when the refinery is run by people who drive to work? Now you have a recursive system. Can you still understand it? Maybe today. By tomorrow it will have changed itself. Can you understand the change?

What happens when you think you understand the change, so you make a prediction, but your prediction affects what happens, making you wrong? But you take this into account when you make your prediction, becoming right again, except now you're a part of the recursive system, and there will never be a right answer. Understanding has become impossible.

Now that's baffling.

(And not to get all political, but this is also why a properly functioning government is not merely a hard, but an intractable problem. No matter how much you know what you're doing, you can't control something that controls you... But that doesn't stop us from trying.)

>>But when she grows up, she learns that everything has a velocity, which has to be some number, so it might as well be high.

It's annoying how you say 'she' because it distracts me from your content into thinking about feminism.

You must get annoyed a lot.

Talk about distraction!

To be perfectly honest, I find your comment well written but I'm not sure what you're saying. (I'm not trying to ignore your comment, there are just many things that I don't feel relate very much to mine. Plus, I've always been pretty bad at reading comprehension :))

So yeah, I'm not sure how this is a red herring. The point is that we take a lot of things for granted and even if each layer of how it gets to work the way it does makes sense, there's always a leap of faith to accept it will work at high speed/volume/scale.

It might sound extremely naive but another way I look at it is that it's… intriguing to see that all of this has been built by human beings. The same kind of beings that make silly mistakes, forget to buy milk, enjoy Jersey Shore… Sure it's built upon centuries of previous results and research, but it still ends up coming from one guy's brain at some point. There's such a gap between the mundane things we do (i.e. mainly the things for our survival) and all the technology and science…

For the electronic-related examples, that means we've been able to ride the speed of light extremely well, while also building components on a microscopic scale. And I find that remarkable for a bunch of (smart) animals.

Yeah, I kind of went off on a tangent there, I don't blame you for not getting all of it :P

I think what I was trying to say in the beginning is that while I understand how it feels like a leap of faith, I don't think it really is. Like when I include a library, on some level I'm assuming it will really function the way the API suggests. But I don't have to take that on faith; I can read through the code, and see what it's actually doing. The code itself is an abstraction of something else, but if I take the time, I can eventually reduce it to an understanding of what's happening on a transistor level. I can't see what's happening in the CPU, but I can understand it.

I can't hold the whole model of my code at a transistor level in my head, but that's the power of abstraction. I understand what's happening on each level on some scale, I understand how the levels interface with each other, so ipso facto I do understand the system as a whole. If it doesn't behave the way I expect, I can use that knowledge figure out why, whether it's because I made the wrong call or because there's a wire disconnected on my motherboard. It's not magical; it just seems that way when I don't pay close attention.

Which is, in fairness, most of the time.

>I think that's a red herring.

>I mean, isn't that just the marvel of abstraction? I can show you how it works, on a basic level: See, it goes around like this. This connects here. That switch opens. This moves back, and that's the behavior that we're looking for. Easy.

>Why is it that when that same thing happens a hundred times a second, the emergent behavior suddenly becomes mind-boggling? It's just the same thing, faster.

I don't think it's a red herring at all. Going faster is more complex, more interesting. A spark plug ignites an air/fuel mixtures, it pushes a piston, which pushes a connecting rod, which turns a crank. That's easy -- once. At 3000 RPM that's 50 times a second, that's not easy, that's complex. It requires timing.

I've hand packed fuel into a canister, ignited it, it goes boom, it moves metal. That's easy. But at 50 times a second it take precision. The spark timing from the distributor has to be right, the crank is connected via timing belt to the camshafts that control the opening and closing of the intake and exhaust valves. That timing has to be right. There's a computer constantly monitors the O2 content of the exhaust gases, so it can better control the air/fuel mixture. There's another sensor to listen for knocking caused by too little air, so it can retard the spark timing to compensate.

All this happens 50 times a second. It's far more amazing than me lighting a fuse and watching something go boom.

But when you dilate time 50 times, isn't it still interesting? Aren't the precise parts still precise? It's more interesting fast because the material properties change, the speed of the springs and the motion of the flame front becomes important-- but that's still fascinating even when you can watch it happen.

And you don't have to slow anything down to see that; controlled demolition, say, deals with the same sort of stuff on a large scale. When you're blowing up a building, what's happening in an individual explosive (hand packed fuel in a canister, with a dumb fuse...) too fast to see isn't important, but you need to pay close attention to the things that happen during seconds, perfectly human timeframes, because they become interesting and complex.

Watching a single revolution of an engine in slow motion, you witness a marvel of engineering taking place before your eyes. But for decades (centuries?) before we understood them, people built engines by trial and error, and watching one of them in slow motion would not have been impressive. It would look sloppy, imprecise, unrefined. Engines today are amazing precisely because they are well understood very slowly, and in practice it mostly works to just say "and then that happens over and over again and that's what pushes you forward."

That understanding is obvious on every scale, whether you're watching high-speed video or just hearing the engine note from outside. That's why I say that the interesting things are still interesting slowed down, and that "it's so fast!" is a red herring.

For me it's plumbing. Flush the toilet, get rid of waste through a hidden underground network and it just works in the middle of a city with millions of people doing it every day.

It also gives me perspective of the enormous debt I owe to (hundreds of) thousands of people "just doing their job" for me to be able to sit where I am and do my part of it. Just from the vantage point of my office chair, the things that surround me have been touched my so incredibly many people during their production and delivery to here.

Plumbing is also one of those things that you don't really think about until something goes wrong with it (in my case, a backup ... ugh).

For those who don't know the Louis CK reference, here is the video: http://www.youtube.com/watch?v=8r1CZTLk-Gk

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