메뉴
HN
Hacker News • 90일 전

현실의 복잡성: 생각보다 놀라울 정도로 많은 디테일

IMP
8/10
핵심 요약

단순해 보이는 물리적, 지식적 작업조차 실제 실행에 옮기면 수많은 예외와 물리적 제약으로 인해 엄청난 복잡성을 지니게 됩니다. 이 글은 계단 만들기라는 사례를 통해 현실이 가진 예상치 못한 디테일을 강조합니다. 이는 복잡한 문제를 해결해야 하는 개발자와 실무자들이 왜 막히고, AI 에이전트가 실제 환경에 적용될 때 왜 어려움을 겪는지 설명하는 핵심적인 통찰을 제공합니다.

번역된 본문

내 아버지는 더 나은 삶을 찾아 18세의 나이로 콜롬비아에서 북미로 이민을 왔다. 나와 내 남동생에게 이는 추운 날씨에 밖에 서 있어야 하는 많은 시간을 의미했다. 아버지가 선호하는 처지 개선 방식은 부동산을 직접 개선하는 것이었고, 우리 형제는 우리가 소유한 건물에서 일하는 것을 돕기 위해 '자발적으로' 징집되었다. 그것이 바로 내가 10대 시절의 상당 부분을 울타리를 교체하고, 참호를 파고, 바닥과 헛간을 짓는 데 보내게 된 이유이다. 그리고 이 모든 건축 작업을 통해 내가 배운 것이 하나 있다면, 그것은 현실에는 놀라울 정도로 많은 디테일이 존재한다는 것이다.

이는 사람들이 왜 지적으로 한계에 부딪히게 되는지 설명해준다. 그들이 문자 그대로 해당 분야에서 세계 최고의 전문가라 할지라도 말이다. 지하실 계단을 짓는 과정을 생각해 보자. 계단은 처음에는 꽤 단순해 보인다. 높은 차원에서 볼 때, 그것은 단지 두 개의 길고 넓은 평행한 나무판자(2" x 12" x 16'), 계단용 발판, 그리고 각 계단 발판을 지탱하기 위한 앵글 브래킷(angle bracket)으로 이루어져 있다.

하지만 실제로 만들기 시작하면 놀라울 정도로 많은 미묘한 차이가 있다는 것을 알게 된다. 가장 먼저 눈치채는 것은 실제로는 꽤 많은 하위 작업들이 있다는 것이다. 거시적인 관점에서도, 2x12 판자의 양끝을 올바른 각도로 자르고; 계단을 고정하기 위해 메인 바닥에 U자형 브래킷을 나사로 조이고; U자형 브래킷에 2x12 판자를 나사로 조이고; 계단을 위한 앵글 브래킷을 부착하고; 그 다음에야 계단 발판을 나사로 조여야 한다. 그 지독한 계단들 말이다.

다음으로 알게 되는 것은 위의 각 단계가 여러 단계로 다시 세분화된다는 것이며, 그중 일부는 재료의 특성, 작업의 성격, 그리고 작업자와 도구의 한계로 인해 까다로운 디테일을 가지고 있다는 점이다. 당신이 직면할 첫 번째 문제는 2x12 판자를 올바른 각도로 자르는 것이 꽤 복잡하다는 것이다. 왜냐하면 올바른 각도를 그려낼 뚜렷한 방법이 없기 때문이다. 창의적으로 접근할 수도 있고(추적하는 방법이 있긴 하다), 삼각법 책을 꺼내서 자르는 각도와 위치를 계산하는 방법을 알아낼 수도 있다. 또한 계단에 적합한 각도가 무엇인지 찾아보고 싶을 것이다. 자를 때 합리적으로 보이는 것과 실제로 안전하게 느껴지는 것은 다를 수 있다. 또한, 자르는 부분이 꽤 곧아야 하므로 원형 톱을 사용할 때 가이드를 부착해야 할 것이다.

작업할 준비가 되면, 계단 판자들을 모두 동일한 각도로 맞추는 것이 결코 쉬운 일이 아님을 빠르게 깨닫게 될 것이다. 메인 보드에 대해 매우 일관되게 각도를 잡아줄 수 있는 무언가가 필요할 것이다. 그것을 갖추고 선을 그었다 하더라도, 똑바로 보였던 판자가 그다지 똑바르지 않다는 사실에 낙담할 수 있다. 목재는 처음에 젖어 있을 때 잘렸다가 지금은 건조해지면서 휘어지기 때문에, 완벽하게 곧은 목재란 없다. 다시 목재 상점으로 돌아가 좀 더 똑바른 2x12 판자를 구하고 선을 다시 그린 후에야 브래킷을 나사로 조이기 시작할 수 있다.

이제 당신은 내가 그은 선에 맞춰 정렬해서 시작했음에도 불구하고, 나사가 완벽히 똑바로 박히지 않아서 결과적으로 앵글 브래킷이 더 이상 완전히 똑바르지 않게 되었고, 이들이 잘못된 각도로 브래킷을 단단히 고정하고 있다는 것을 배우게 될 것이다. 먼저 가이드 구멍을 뚫어 이 문제를 해결할 수 있다. 또한, 동일한 구멍에 나사를 두 번 다르게 박는 것은 사실상 불가능하기 때문에 1인치 정도 옆으로 옮겨서 박아야 할 것이다.

이제 마침내 계단 발판을 나사로 조일 준비가 되었다. 만약 나사가 2인치보다 길다면 다른 것으로 교체해야 한다. 그렇지 않으면 나사가 판자 상단을 뚫고 나와 당신의 발을 찌를 것이다.

모든 단계와 모든 수준에는 물리적 결과를 초래하는 디테일들이 넘쳐난다. '그래서 뭐?'라고 생각하며 이러한 세부 사항을 계단 목수 일의 우연한 산물이나 특수성으로 치부해버리고 싶은 유혹이 든다. 그리고 그것은 계단 목수 일에 국한된 특수성이 맞다. 바로 그렇기 때문에 그것들을 '디테일'이라고 부르는 것이다. 하지만 의미 있는 디테일이 놀라울 정도로 많이 존재한다는 사실 자체는 결코 특정 분야에만 국한된 것이 아니다.

원문 보기
원문 보기 (영어)
John Salvatier Reality has a surprising amount of detail 13 May 2017 I. My dad emigrated from Colombia to North America when he was 18 looking looking for a better life. For my brother and I that meant a lot of standing outside in the cold. My dad’s preferred method of improving his lot was improving lots, and my brother and I were “voluntarily” recruited to help working on the buildings we owned. That’s how I came to spend a substantial part of my teenage years replacing fences, digging trenches, and building flooring and sheds. And if there’s one thing I’ve learned from all this building, it’s that reality has a surprising amount of detail. This turns out to explain why its so easy for people to end up intellectually stuck. Even when they’re literally the best in the world in their field. Consider building some basement stairs for a moment. Stairs seem pretty simple at first, and at a high level they are simple, just two long, wide parallel boards (2” x 12” x 16’), some boards for the stairs and an angle bracket on each side to hold up each stair. But as you actually start building you’ll find there’s a surprising amount of nuance. The first thing you’ll notice is that there are actually quite a few subtasks. Even at a high level, you have to cut both ends of the 2x12s at the correct angles; then screw in some u-brackets to the main floor to hold the stairs in place; then screw in the 2x12s into the u-brackets; then attach the angle brackets for the stairs; then screw in the stairs. Those goddamn stairs. Next you’ll notice that each of those steps above decomposes into several steps, some of which have some tricky details to them due to the properties of the materials and task and the limitations of yourself and your tools. The first problem you’ll encounter is that cutting your 2x12s to the right angle is a bit complicated because there’s no obvious way to trace the correct angles. You can either get creative (there is a way to trace it), or you can bust out your trig book and figure out how to calculate the angle and position of the cuts. You’ll probably also want to look up what are reasonable angles for stairs. What looks reasonable when you’re cutting and what feels safe can be different. Also, you’re probably going to want to attach a guide for your circular saw when cutting the angle on the 2x12s because the cut has to be pretty straight. When you’re ready to you will quickly find that getting the stair boards at all the same angle is non-trivial. You’re going to need something that can give you an angle to the main board very consistently. Once you have that, and you’ve drawn your lines, you may be dismayed to discover that your straight looking board is not that straight. Lumber warps after it’s made because it was cut when it was new and wet and now it’s dryer, so no lumber is perfectly straight. Once you’ve gone back to the lumber store and gotten some straighter 2x12s and redrawn your lines, you can start screwing in your brackets. Now you’ll learn that despite starting aligned with the lines you drew, after screwing them in, your angle brackets are no longer quite straight because the screws didn’t go in quite straight and now they tightly secure the bracket at the wrong angle. You can fix that by drilling guide holes first. Also you’ll have to move them an inch or so because it’s more or less impossible to get a screw to go in differently than it did the first time in the same hole. Now you’re finally ready to screw in the stair boards. If your screws are longer than 2”, you’ll need different ones, otherwise they will poke out the top of the board and stab you in the foot. At every step and every level there’s an abundance of detail with material consequences. It’s tempting to think ‘So what?’ and dismiss these details as incidental or specific to stair carpentry. And they are specific to stair carpentry; that’s what makes them details. But the existence of a surprising number of meaningful details is not specific to stairs. Surprising detail is a near universal property of getting up close and personal with reality. You can see this everywhere if you look. For example, you’ve probably had the experience of doing something for the first time, maybe growing vegetables or using a Haskell package for the first time, and being frustrated by how many annoying snags there were. Then you got more practice and then you told yourself ‘man, it was so simple all along, I don’t know why I had so much trouble’. We run into a fundamental property of the universe and mistake it for a personal failing. If you’re a programmer, you might think that the fiddliness of programming is a special feature of programming, but really it’s that everything is fiddly, but you only notice the fiddliness when you’re new, and in programming you do new things more often. You might think the fiddly detailiness of things is limited to human centric domains, and that physics itself is simple and elegant. That’s true in some sense – the physical laws themselves tend to be quite simple – but the manifestation of those laws is often complex and counterintuitive. II. Boiling A Watched Pot Consider the boiling of water. That’s straightforward, water boils at 100 °C, right? Well the stairs seemed simple too, so let’s double check. Put yourself in the shoes of someone at the start of the 1800’s, with only a crude, unmarked mercury thermometer, trying to figure the physics of temperature. Go to your stove, put some water in a pot, start heating some water, and pay attention as it heats. (I suggest actually doing this) The first thing you’ll probably notice is a lot of small bubbles gathering on the surface of the pot. Is that boiling? The water’s not that hot yet; you can still even stick your finger in. Then the bubbles will appear faster and start rising, but they somehow seem ‘unboiling’. Then you’ll start to see little bubble storms in patches, and you start to hear a hissing noise. Is that Boiling? Sort of? It doesn’t really look like boiling. The bubble storms grow larger and start releasing bigger bubbles. Eventually the bubbles get big and the surface of the water grows turbulent as the bubbles begin to make it to the surface. Finally we seem to have reached real boiling. I guess this is the boiling point? That seems kind of weird, what were the things that happened earlier if not boiling. To make matters worse, if you’d used a glass pot instead of a metal one, the water would boil at a higher temperature. If you cleaned the glass vessel with sulfuric acid, to remove any residue, you’d find that you can heat water substantially more before it boils and when it does boil it boils in little explosions of boiling and the temperature fluctuates unstably. Worse still, if you trap a drop of water between two other liquids and heat it, you can raise the temperature to at least 300 °C with nothing happening. That kind of makes a mockery of the statement ‘water boils at 100 °C’. It turns out that ‘boiling’ is a lot more complicated than you thought. This surprising amount of detail is is not limited to “human” or “complicated” domains, it is a near universal property of everything from space travel to sewing, to your internal experience of your own mind. III. Invisible vs. Transparent Detail And Getting Intellectually Stuck Again, you might think ‘So what? I guess things are complicated but I can just notice the details as I run into them; no need to think specifically about this’. And if you are doing things that are relatively simple, things that humanity has been doing for a long time, this is often true. But if you’re trying to do difficult things, things which are not known to be possible, it is not true. The more difficult your mission, the more details there will be that are critical to understand for success. You might hope that these surprising details are irrelevant to your mission, but not so. Some of them will end up being key. Wood’s tendency to warp means it’s mor