
Reality has a surprising amount of detail (2017) - rgun
http://johnsalvatier.org/blog/2017/reality-has-a-surprising-amount-of-detail
======
DanielBMarkham
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, surveys,
facts -- whatever you need.

Everybody knows everything. It's quite amazing. And then when you take a tech
team into an unknown domain, suddenly they find it very difficult to open up,
admit ignorance, and reason about things.

I am reminded of some startup book or blog I read years ago. It was talking
about the relationship between intelligence and startup success. The author
said that there was a correlation. It was an _inverse_ correlation. The more
you have been rewarded in life for being smart and knowing everything, the
more you felt intelligent, the less chance you had of making a startup work.
You just weren't able to admit all the things you didn't know.

~~~
codingdave
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.

~~~
shoover
It is absurd how people actually do this all the time in Amazon product
questions. Will it work with my Samsung phone? "I don't know." Does it come
with batteries? "I think it did."

~~~
harpiaharpyja
I'm guessing that's because Amazon sends out emails explicitly asking people
to answer questions on their past purchases. And for some reason, this makes
some subset of people feel obligated to reply even though it makes no sense.

~~~
shoover
I think you're right. That sounds exactly like something amazon would do and
how people would respond. I must have turned those emails off, which makes
seeing the answers utterly stupefying.

~~~
bittercynic
To give customers the benefit of the doubt: Some may know exactly what's going
on, and enjoy making Amazon look stupid by posting those replies.

~~~
shoover
That reply doesn’t suit your handle at all ;)

------
sly010
A few years ago I co-founded a standing desk company without any experience in
real world products in general. The plan was to source desks and sell them to
companies. How complicated could it be? Well, the freight company requires a
lot of information about the destination building. The destination building
require a lot of paperwork in a very specific format just to deliver
something. The paperwork is always a little different. Then actual delivery
need to be scheduled on the phone. Every time. The pallets don't fit in the
elevator after all, so need men to move boxes. Someone need to dispose of the
pallets. The building doesn't have large item disposal. To assemble 60 desks
we need men, tools, floor-plan, access to the building, etc. Someone has to
clean up the packaging material. Then of course one of the 60 boxes were
dropped, now damaged and needs replacing. Sending one box is a different game
than sending 60. Even if you know what you are doing it takes a lot of emails
and phone calls to outfit an office with furniture, and somehow everyone wants
to communicate over phone or email, so automation is impossible. And that's
how my e-commerce company turned into a service business wiped out all my
profits :) (edited for typos)

~~~
le-mark
If you're like my old boss, just tell the employees to assemble their own
desks, and then wonder why all these developers who requested a standing desk,
are still using their old sit down desks.

~~~
Johnny555
I'd be happy to assemble all of my office furniture if my company paid for it
-- though paying $100+/hour engineers to do the work of a $15+ handyman seems
like a bad deal for the company - especially when the guy that assembles desks
all day will do it faster (and correctly).

~~~
skybrian
Consider it a team-building exercise? Companies waste employee time in all
sorts of other ways, so why not building desks?

~~~
nugator
We did exactly this where I'm an expensive consultant. The one who assembled
his table the fastest won a prize. My workplace might be a little different
but we also are responsible for moving the dishes in and out of the
dishwasher. I'm happy to do it.

------
nlawalker
This is such a good explanation of why I have a hard time working with folks
who always approach technical problems with the attitude of "why don't we just
do this?"

It's the _just_ that gets me. They are too action-oriented to think about the
details or ask someone who's done it before, so they start down the path of
(to use the author's metaphor) buying cheap lumber and calculating the angles
for cutting the stair boards. They follow through with that and finish the
rest of the stairs with the same attitude.

Now the stairs are finished and installed (shipped) - they look terrible,
they're wobbly and too steep and everyone who walks on them in either
direction trips. Then begins the never-ending process of in-place
improvements: using a sander to even out the angles, grinding down the too-
long screws that stick up, pounding on warped boards to straighten them out.
We can't fix the angle or the poor spacing of the steps though, because
everyone's gotten perversely used to it.

When the whole house gets built this way, you live in a perpetual fixer-upper,
where each component is either under revision or you've settled for it being
"good enough" until enough work has been done to make everything else a little
less broken.

~~~
debt
"they look terrible"

Well then don't do a shitty job? I mean if the budget is there, then yeah,
_just_ build me some stairs.

~~~
platz
Are you a product manager?

~~~
zawerf
You might be saying this in jest but his statement is totally valid if he is a
manager.

The level of abstraction you are working on matters. A manager can't _just_
build a great business either. But for example if he encounters legal trouble,
he can _just_ hire lawyers to fix it.

His interface to the world is via delegation to people who can solve his
subproblems competently and consistently. There's still a "surprising amount
of detail" but at a higher abstraction level and solved with different tools(a
really strong "biological" AI that can resolve and prevent the details from
bubbling up :P).

------
jasode
_> Do you remember the insights that were crucial in learning to ride a bike
or drive?_

The author mentioned bicycles and inadvertently missed an opportunity to show
another "unknown reality" that beautifully illustrates his point.

Consider typical adults (not physicists) with 20+ years of bicycle riding. If
you ask them, _" how does a bicycle turn?"_, they'd respond that _" you just
lean into the direction of the turn and it turns."_

But that's not the complete picture of what actually happens.[1] If you were
to capture the bicyclists with a high-speed camera, you'd notice that there's
always a micro movement of _countersteering_ to make the bike momentarily lose
its balance and "fall into" the turn. Then there's an immediate correction of
the steering to match the turn. This all happens in the span of milliseconds.

Even though the human body "discovered" the countersteering by way of
kinesthetic feedback, the bicyclists' brains don't explicitly communicate this
intermediate step to others. (Tacit knowledge.[2])

It's not always the case that we "simplify" reality for innocent purposes of
pedagogy. (E.g. we tell "lies" to children about "numbers", "functions", etc
and as they get older, we successively remove the layers of lies as they get
into high school and college math.) Instead, we often don't even _know_ the
reality (e.g. bicycle countersteering) to consciously omit it.

That extra reality may not even be important. If one human is teaching another
human, you can leave the "countersteering" detail out and it won't matter. The
200 years of people learning how to ride bicycles is evidence of that.
However, if you're a robotics scientist and want to build a self-driven
motorcycle, the reality of countersteering becomes a crucial detail.

[1]
[https://www.youtube.com/watch?v=llRkf1fnNDM](https://www.youtube.com/watch?v=llRkf1fnNDM)

[2]
[https://en.wikipedia.org/wiki/Tacit_knowledge](https://en.wikipedia.org/wiki/Tacit_knowledge)

~~~
tome
Have you actually tried turning a bicycle without countersteering? I have, the
last time the topic was discussed on HN. I found I was able to turn without
any perceptible countersteer. It's technically _possible_ that I do have to
countersteer for a small number of miliseconds over a small number of
milimeters, but my experience leads me to doubt it.

~~~
monochromatic
A moped (and I assume a motorcycle) is a lot harder to turn without
countersteering. I’m not sure if that’s because it’s more massive or what.

Anyway, learning to ride a moped was when I first consciously discovered
countersteering. It made things a lot easier after that point.

~~~
hornbaker
It could be based on speed rather than mass. Above 5-10 mph or so, you turn a
motorcycle with pretty much total countersteering, forcefully pushing forward
on the inside hand grip to get the motorcycle to lean over. The faster you're
going, the further you need to lean the motorcycle.

~~~
monochromatic
That makes sense too.

------
KineticLensman
There is an excellent example of this type of fiddly detail in Liz England's
2014 blog post about the problems of doors in video games [0]. She identifies
about 20 questions you can ask about as a door (as a game designer) and then
about 30 different roles (from sound designers [1] to monetization
director[2]) who might be involved. Her post works really well because the
example is so mundane but the questions are very valid.

[0] [http://www.lizengland.com/blog/2014/04/the-door-
problem/](http://www.lizengland.com/blog/2014/04/the-door-problem/)

[1] "I made the sounds the door creates when it opens and closes."

[2] "We could charge the player $.99 to open the door now, or wait 24 hours
for it to open automatically"

~~~
woliveirajr
> Network Programmer: “Do all the players need to see the door open at the
> same time?”

Brings me the question on wheter the "reality" is the same for everybody.

~~~
cicero
Perception of reality is not the same for everybody, but there is a single
objective reality that we all perceive in our imperfect ways.

~~~
akvadrako
That is just speculation. Maybe the only things that exist are subjective
perceptions and they don't all overlap. Then the objective reality only exists
from god's viewpoint, so if there's no god...

~~~
cicero
If there is no objective reality, then what is the explanation for the overlap
of our subjective experiences? By the way, you do bring up a good reason for
the existence of God as the only one who knows all of reality. However, God
does not know reality by perception. Rather, God is the source of reality, so
he knows it because it begins in his mind.

------
larrik
I've actually built a few staircases, and it's a _ton_ harder than it even
sounds here. In fact, there's apparently carpentry competitions and building a
stairway to code is the grand finale.

The way he does it, with the angle brackets? That's the easiest way, and by
far the weakest. The strongest way is to notch out 2x12's (ideally at least 3,
with one in the middle). Oh, and no step can be more than 1/8" difference in
rise vs _any_ other stair. This much harder, though.

Combine this with the math to know how many steps you need, and what angle the
stairs need to lean overall (this one he touches on), and it's a real pain.
Fail, and people get hurt. Your body is pretty sensitive to stairs being
perfect.

~~~
twothamendment
Don't forget stairs that land on surface that is sloped from one side of the
stairs to the other. What height should that bottom step be? Will the
inspector measure both sides? Do you shoot for the middle being right on and
each side being a bit too high and a bit too low?

Watch the height on the first and last steps. The middle ones are the "easy"
ones.

In bigger cities there are companies that only frame stairs. It is amazing to
watch them - they can do it in their sleep. I watched one crew finish up some
complex stairs in less time than our framing crew would have spent making a
game plan.

There is detail in everything and until you've done that job you really don't
notice it.

~~~
aaronblohowiak
I've heard the "real fun" in stairmaking is spiral staircases where the radius
changes throughout the staircase...

------
CurtMonash
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 me if I am.

2\. A student gets and assignment to write an essay about a particular brick
wall. He can't see how to fill the assigned length with anything interesting.

The instructor then says OK, write instead only about the left-topmost brick.
The student has so much to say about it he has trouble making his essay SHORT
enough to meet the assignment's requirements.

~~~
dsr_
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

~~~
falcolas
Err, Bozeman doesn't have an opera house. Certainly not one with a burger
stand across Main Street.

Just sayin'

;)

~~~
Recursing
Maybe there used to be one?
[https://www.bozemandailychronicle.com/opinions/a-number-
of-y...](https://www.bozemandailychronicle.com/opinions/a-number-of-years-ago-
the-old-bozeman-opera-house/article_12ce5147-0718-5768-9a0d-924bd73bf04a.html)

~~~
falcolas
!

I learn the damndest things every day. Thank you for a slice of history of my
own home town.

It _is_ a nice little park (and still there).

------
katzgrau
I've thought about this too, and generalizing to one more degree, I believe it
comes down to perspective. The details are what keep you locked in that
perspective.

It's difficult, but invaluable, to truly see things from other perspectives.
Once we begin learning the small details of one perspective, our minds seem to
develop heuristics for quickly judging all things from that perspective.
Attempting to see things from a different perspective slows us down and makes
us uncomfortable.

Citation needed, but I sincerely believe our intellectual difference are just
a consequence of viewing things through many layers of varied perspectives. So
for people who have considered global warming and believe it to be false, it
really is false. That _is_ reality. It's all subjective.

~~~
pas
Hawking uses the phrase "model dependent realism" for the small subatomic
world.

But of course it's perfectly valid for our highly complex human scale world
too. And then why do we think the Sun is what we see in pictures? Of course
it's that, but it's much more too, and since we don't capture a lot of that in
our models (be them photos in various EM gamuts or neutrino counts or whatever
numbers), but we only see the surface, we will never experience it up close.

And the same goes for our experience of others' experiences, be it scholarly
undertaking in unraveling the mysteries of Earth or simple
carpentry/masonry/woodworking/sports.

Even though hundreds of millions of people watch and tens of millions play
soccer, no one really has the correct model about playing it on the
professional (world cup, UK Premier League) level. Yet every one has a model
of soccer, and of course that's their day to day reality. (And they of course
do some imperfect subconscious belief update on their models as they go
through life, but that's not much compared to an actual rational inquiry using
the scientific method - but who has time for that for _everything_ in the
world?)

------
foxhop
This is an incredible read, very thought invoking.

I've never replaced stairs but I have learned enough of the "details" by
repairing them (or being aware of them) to know it's a really hard to get
right.

A single 1/4 inch difference between two steps can feel wrong; a 1/2 inch
difference and people will likely stumble or tumble down them on their first
approach. Our intuition and pattern recognition impacts how we solve problems.
Some call it "muscle memory" but it's not just in our muscles, it's in our
unconscious thought.

Like the author explains so well, once we move a detail into our unconscious
it becomes part of us, transparent to us, "common sense"; and an unnoticed
detail is completely hidden from us.

The details of reality can only be taught through experience, because once
understood, they move almost instantly from hidden -> transparent.

~~~
hornbaker
A gif of what happens when one step is just slightly too high:

[https://imgur.com/hl3YWJD](https://imgur.com/hl3YWJD)

~~~
asavadatti
Also interesting how people speed up after tripping.

~~~
foxhop
I had an over weight friend in highschool who could run really fast. He did
this by basically by making his top half fall forward which caused his legs to
move quickly to keep him from landing on his face.

I think this is a similar phenomenon where the people tripping up the stairs
have an imbalance causing their top half to fall forward. As a result the
unconsciously speed their bottom half up to catch the top half from falling.

------
zzzeek
Here's what I think the most chilling takeaway is. People who have no
appreciation for details _do not know anything_. They are dangerous people who
will conclude incorrect things with certainty on a regular basis.

~~~
krick
I would love to agree, because I always cared for details deeply. How can it
be a bad personality trait? But later I started to reconsider that. The most
effective high-level managers I know outrageously little care for details, as
it seemed to me. When I was their subordinate it caused me a great deal of a
problem.

But then it dawned on me. Things somehow play out well in the end. Why? Well,
because there I was, to care for details, to find solutions for what it seemed
like an impossible problem to solve. If they cared for details as much as I
did — we wouldn't even begin anything, because the amount of detail was so
overwhelming. The general plan wouldn't be born in the first place.

Now I sometimes wish I could care less for details and try to be... well,
easier, I guess.

~~~
zzzeek
those managers had to care for at least the _existence_ of details if they
allowed you to do what was needed to honor those details. A truly "I dont care
about details" manager would ask you to do something, you'd explain it cant be
done that way for X, Y, Z, etc., and they'd say, "I don't care, do it anyway".
A manager might not know the details of the thing you are doing for them, but
they need to have an appreciation that details _exist_ , which probably means
they know about details from some other field they've been involved in, like
sports, carpentry, art, or something else like that, such that they understand
when someone says, "we need to do it this way because X, Y, Z", they know that
those are details, you know them, and that's important to honor.

------
simias
This article points out exactly why even though I like to tinker with a lot of
stuff my main hobby is always programming. Because programming is more akin to
writing down maths than building a staircase. Algorithms don't warp because of
humidity, algorithms don't have leakage current. Sure computers have their
quirks (overflows, floating point issues, UB etc...) but it's still a finite
amount of knowledge unlike the infinite amount of details of reality.

An other pleasant part of software development is that all you need is a
computer and a compiler/interpreter to get started. No need to buy dedicated
tools or supplies. And if you realize halfway into a project that you did
something wrong (that your "staircase" is not cut right) then you can easily
undo and redo anything without any mess or waste. No cleanup needed either.
The only limits are your skills and imagination.

~~~
slfnflctd
In fun, a contrary perspective: at least with woodworking tools, they don't
become obsolete in 2-5 years just from laying dormant on the shelf!

Seriously, though, couldn't agree more, I've said some variation on everything
you mentioned for many years. Especially the mess part. I would add the risk
of personal injury, too.

~~~
ballenf
Improperly cared for, however, and they will rust or worse.

Over longer time spans, the tools sometimes become outdated in terms of one's
productivity while using, assuming non-artistic motivation for use.

Old motorized tools are more prone to this than mechanical-type tools. Which
maybe gives some insight as to the factors that contribute to obsolescence.
There are exceptions, of course, but generally my grandfather's hand tools are
still perfectly serviceable while his motorized tools often have more
drawbacks than benefits to use. A 50-year circular saw is as heavy as a boat
anchor and is a huge pain in the ass to adjust and use compared to newer
options.

------
fb03
I'd say "fiddliness" is a characteristic of happiness and focused work.

If you overlook most details you are basically just 'doing stuff to get
objectives done', which is meager imho.

Getting acquainted with detail takes us away from the vast sameness that we
experience when we are just running on automatic and helps us cherish and
savor each moment as complexity unfurls.

~~~
mratzloff
I think you really hit on something here. Anytime I'm working on a hobby of
mine, I like to actively get into the weeds (figuratively, occasionally
literally). It's in exploring and learning about the depth of the unknown that
I find the most enjoyment.

I learned to love talking to strangers when I realized the richness and
variety of human experience is so vast that no one person can feel or
experience everything another person can in their lifetime. In retrospect,
it's amazing I had to realize this at all, but we all start out self-absorbed.

~~~
fb03
It's probably when you're into those small universes, chasing down detail,
that you are most happy and comfortable, even tho you might not be at that
specific time your most productive self. After all, when 'flow' happens, We
are not really caring about the passage of time, right? ;)

------
mojuba
Two things that came to mind while reading this essay:

\- The effect of a surprise when facing unexpected complications/details is
because our brains tend to simplify things, or rather simplify the model of
the world that we maintain. When you first hear that water boils at 100º your
brain really really wants to assume it's that simple, no more than that.
Simplifications are crucial for optimising the brain's power consumption,
which it tends to minimize all the time.

\- The amount of detail in human built stuff, as well as in our understanding
of the world is a result of many centuries of perfecting and improving those
things. Go a few millenia back and look at the stairs we were building then,
they were awful. Or the fact that the process of boiling is so complex is a
result of relatively recent discoveries in physics, just a few centuries ago.

Funny thing is, the details of the reality around us will only get more
complex over time. Suppose in a few centuries from now stairs will be so
complex and so perfect that no individual will be able to build them on their
own.

~~~
logfromblammo
_Pure_ water boils at 100 ºC, _in an environment at standard temperature and
pressure, with sufficient vapor bubble nucleation sites_.

If you're a cook, you don't really need to know all that, because you either
live up in the mountains (at lower pressure) or you don't. You either have
hard water (with more dissolved ions) or you don't. And your pots are never
scrubbed _perfectly_ clean.

Suppose that in a few centuries, stairs will have to account for different
numbers of legs, or wheels, or different foot types, or varying amounts of
gravity, or track gauge, or crystal habit, or effect on convection and
ventilation, or whether classical Earth-standard humans will ever be expected
to use them.

------
franciscop
This resonates so well with Engineering in an unexpected way for me: the
"production" version is orders of magnitude harder than the prototype. I kist
expected it to be plainly harder.

I'm not talking just about programming. At my University I used to make robot
arms and RC stuff with my classmates. Polystyrene, Arduino and a lot of duck
tape were our friends, winning even a NASA competition. It was actually quite
fun and fairly easy.

After finishing and while I was freelancing, I tried to take it to the next
level. Once you get to rigid pieces and tight couplings, there is a huge
amount of details and gears that I don't even know how to start searching for.
What I learned at my University (Industrial Engineering) won't work as well,
since I am not ready to order 10000s of pieces.

------
serpix
This here is why estimation of tasks (in software) is IMHO futile hand waving.
There is always unknown unknowns, snags and hangups which may surprise
everyone.

Everybody who actually creates or makes something can agree that that stuff is
hard, really hard but oh so rewarding!

~~~
TremendousJudge
the point of good estimation is not the estimation itself (which is not very
reliable), but actually thinking about what the details of the task are. I
think the estimation should be seen as an excuse to partake in this exercise

------
tpaschalis
Awesome post! Personally, I've experienced this in academia, with me being the
culprit but also in a team setting. Fresh graduates, seem to be convinced that
their narrow-scope textbook knowledge can conquer the world! I've _studied_
Electromagnetism, one would exclaim! How hard can the software implementation
be? Why should I bother with technicalities such noise introduced by the cable
setup?

The moment you take a step back, realize that a real-world project has so many
details, that your team can get collectively stuck, and that you might be just
flat out _wrong_ is really humbling.

------
pbhjpbhj
The suggestion to simply try and notice more detail seems tantamount to
advising "just do it better".

Why not ask someone who has done it before, or who does it for a living. There
are many domains of human endeavour, but few with no experts. Experience is
not necessarily expertise, but the experienced know what details to look for
even if they don't know how to fix them.

That to me is another problem of capitalism - people reserve knowledge in
order to attract finance with its value; whilst the greatest good is to share
that knowledge.

~~~
lamename
Agreed. But I interpreted part of his point to be: seek out the perspectives
of others to help you notice new details.

------
skolos
> 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.

Actually nominal 2 inch lumber has thickness of 1.5" [1]. So your screws
should be shorter than 1.5".

[1] [https://www.archtoolbox.com/materials-systems/wood-
plastic-c...](https://www.archtoolbox.com/materials-systems/wood-plastic-
composites/dimensional-lumber-sizes-nominal-vs-actual.html)

~~~
TeMPOraL
> _Actually nominal 2 inch lumber has thickness of 1.5 "_

And, as I've recently learned, two-by-four is in fact 1½ × 3½ inches.

How on Earth does that make sense? Why do people call things as if they were
X, while knowing perfectly well they're not X? Is this an American thing?

~~~
wetmore
2x4 lumber is cut into rough boards in the milling process which are actually
2 by 4. These are dried (at which point they shrink) and planed (the wood will
warp a bit during the drying process, jointing and planing will help correct
this) so the resulting boards are smaller than their original 2x4 size.

Some more surprising detail in reality :)

~~~
TeMPOraL
Heh. I feel that reality is just that beautiful, never-ending fractal of
annoyance...

------
goatlover
And this is the reason I'm somewhat skeptical of predictions of future
superhuman AI. The world is complicated and full of all kinds of details we
overlook. Creating a general purpose AI that's able to bootstrap itself to
being better than all humans at everything seems like ignoring all the
difficulties it will run into. It's easy to imagine when not taking everything
into account, but extremely hard to realize.

And it's also why I think he paperclip maximizer and gray goo scenarios are
silly. Maybe it's theoretically possible to create something that would eat
the world, but in order to do so, it would have to overcome every obstacle the
world throws at it. Again, easy to imagine, extremely hard to realize. All
those details get in the way.

~~~
hwillis
If anything it should make you feel the opposite. The brain is an extremely
effective optimizer that solves these problems in a way that is opaque to us.
We find it very difficult to solve them.

An AI is an "unlocked" brain. It can see all the things that it does and then
see how it does them. If it learns to ride a bike -and if it's a humanlike AI,
it will be able to- it'll be able to see exactly what it does and build a
model from that. We would be able to do the exact same except we can't see
inside our own brains and we have to study slow motion video and notice every
little thing. The AI just sees oh, I turn the other direction slightly before
initiating a turn. Voila, countersteering is discovered.

~~~
goatlover
> An AI is an "unlocked" brain. It can see all the things that it does and
> then see how it does them.

Except this AI doesn't exist. You're imagining there is such a technology, and
this technology will just be able to see all the detail in the world it needs
to learn, and presto it does everything better than opaque humans.

If you think deep learning is such a technology, then ask yourself to what
extent ANNs understand themselves and you'll see they don't at all. They're
just good at optimizing for certain problems humans are able to set them up
for.

So, how will us opaque humans create such a transparent technology?

~~~
hwillis
> Except this AI doesn't exist. You're imagining there is such a technology,
> and this technology will just be able to see all the detail in the world it
> needs to learn

Obviously I'm imagining it. Strong AI does not yet exist. It's also obvious
that it _could_ exist, because humans do it. I'm only making two logical
inferences here:

1: Future superhuman AI will have at least the capabilities of the human
brain, because we know those abilities are possible, because we do them.

2\. A future superhuman AI will have the ability to examine itself in memory
and identify things about itself in a way that far exceeds human
introspection: we can barely examine out own emotions, much less the actual
neuronal contents of our heads.

> And it's also why I think he paperclip maximizer and gray goo scenarios are
> silly. Maybe it's theoretically possible to create something that would eat
> the world, but in order to do so, it would have to overcome every obstacle
> the world throws at it. [...] If you think deep learning is such a
> technology, then ask yourself to what extent ANNs understand themselves and
> you'll see they don't at all.

Well first off, they're quite good at it[1], but more importantly that's weak
AI rather than strong AI. Arguing that weak AI is unlikely to be superhuman is
plausible, but strong AI is definitely self-improving.

What I think you're saying is that you're skeptical of us being able to create
strong AI out of current techniques, which is also reasonable. NN are not
gonna evolve into skynet any time soon. But believing them to be categorically
impossible requires the human brain to be special in some way- either beyond
human comprehension or comprising a supernatural component.

[1]:
[https://en.wikipedia.org/wiki/Generative_adversarial_network](https://en.wikipedia.org/wiki/Generative_adversarial_network)

~~~
goatlover
I'm skeptical that strong AI will be superhuman in a way that allows it to do
much better than the entire human race at any task.

In context of the OP, the issue is all the detail in the world that takes many
people over ages to work out. Will the superhuman AI be able to recognize all
the detail it needs to know to accomplish tasks better than us (all humans)?
Notice this isn't the same issue as being transparently intelligent.

~~~
hwillis
> In context of the OP, the issue is all the detail in the world that takes
> many people over ages to work out. Will the superhuman AI be able to
> recognize all the detail it needs to know to accomplish tasks better than us
> (all humans)?

Yes, if for no other reason than this:
[http://slatestarcodex.com/2017/11/09/ars-longa-vita-
brevis/](http://slatestarcodex.com/2017/11/09/ars-longa-vita-brevis/)

------
lazyjones
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 suitable for stairs at just the right
angles and with holes drilled at optimal positions!

Standardising and having a limited set of (appropriate, well-understood)
choices at every level is key to building complex projects. Which is probably
one of the reasons why software quality isn't really improving...

~~~
zaphar
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.

~~~
lazyjones
Same here. But I find code reuse problematic: people tend to build large
libraries with complex APIs and too many options (typically also lacking sane
defaults) instead of small, focused code "blocks" that can be well understood
and tested and do one single thing very well. It's like having to fasten a nut
and being offered 3 types of swiss army knives as your available tools. Same
with operating systems, web development frameworks etc. ... Too many options,
too little thorough understanding, stable interfaces.

------
hyperpallium
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.

------
SAI_Peregrinus
I am reminded of three texts: "Foundations of Mechanical Accuracy" by Wayne R.
Moore[1], Tektronix's "Low Level Measurement Handbook"[2] and LTC Application
Note 47 "High Speed Amplifier Techniques"[3]. All three deal with systems at
the limits of precision, whether mechanical, electrical, or temporal.

Say you want to measure a length. Easy right? Just take a measuring tape or
ruler and put it next to the thing to be measured. But what if you need really
high accuracy over a reasonably long distance. Say, to within a tenth of a
millimeter (100 μ) over a meter long distance or more. Now temperature
matters: your scale will expand differently than the object being measured if
they aren't the same material. Humidity has similar effects. Traditional
length standards were metal bars, but metal bars sag under their own weight,
changing the distance between the ends. Modern standards use interferometers
to create a length standard, but those require very good mirrors and
monochromatic light sources for proper operation. That's without getting into
electronic measurement systems for the interferometers, and the required
sensitivity there...

And you still need a way to transfer the accuracy from the interferometer to a
practical measuring scale. That brings back concerns of temperature. Human
handlers transfer heat, leading to local expansion. Light is absorbed
differently by objects of different color, leading to different expansion.
Etc.

The further you try to push the accuracy and precision the more details start
to matter, and the more disciplines start to get involved.

[1]
[http://mooretool.com/publications.html](http://mooretool.com/publications.html)
(it can be found on Gen Lib, but is worth the price)

[2] [https://www.tek.com/document/handbook/low-level-
measurements...](https://www.tek.com/document/handbook/low-level-measurements-
handbook)

[3] [https://cds.linear.com/docs/en/application-
note/an47fa.pdf](https://cds.linear.com/docs/en/application-note/an47fa.pdf)

~~~
wetmore
Reminds me of the difficulty of measuring the heights of mountains like
Everest.

------
zafka
I really love the title of this essay. The essay itself and the comments are
also delightful. I am going to start using this at my job (where I write
embedded code for medical devices). This fact gets so much more apparent when
code gets put in production devices, and you see the affect of tolerance
stack-ups of hundreds of parts. I also think this is why i feel very
optimistic about finding new and exciting things in the world. So many people
accept the reality of things that someone has explained, while there are
actually many variations yet to be revealed.

------
tempestn
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 disclaimer if I'm wrong (aka
missing an important detail!) or a brag if I'm right; it's intended as the
former!

~~~
cricalix
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.

~~~
unavoidable
Another problem with reality: most wall-floor angles are not exactly 90
degrees! Anyone who has tried to build custom cabinetry and shelving can
attest to this.

------
jpfed
>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.

Wait, do programmers actually think that programming is fiddly? The fiddly
part is always the concerns of the real-world domain; what's special to
programming is the ability to use _abstractions_.

~~~
TeMPOraL
Abstractions are, in their way, new things, and introduce further fiddliness.

Consider these pieces of eternal wisdom from our industry:

\- [https://www.stilldrinking.org/programming-
sucks](https://www.stilldrinking.org/programming-sucks)

\- [https://medium.com/message/everything-is-
broken-81e5f33a24e1](https://medium.com/message/everything-is-
broken-81e5f33a24e1)

The author suggests that similar problems are a feature of pretty much
everything humans do.

------
YeGoblynQueenne
>> If you’re trying to do impossible things, this effect should chill you to
your bones. It means you could be intellectually stuck right at this very
moment, with the evidence right in front of your face and you just can’t see
it.

I know this article is not about AI, even remotely- but, oh my dog, it so
_is_. It's like, you can do really well if you carefully select the borders of
your problem domain- ImageNet, Go, Phenix, AZ; but when you try to use the
same super powerful tools in an unconstrained situation (imagine a self-
driving car in Mumbai; or playing Warcraft) then all those little noisy,
unpredictable, unmodellable details in the real world kick your models'
accuracy to the curb.

In fact, I think most AI folks have figured this out by now and that this
realisation is a very big reason why AI has advanced with leaps and bounds in
recent years. But we're still up against impossible odds here.

And this should be put to the attention of the Singularitarians- you don't
know what you don't know yet. It might look like things are about to go
exponential, but you never know what's behind the next bend. As Solon said to
Croesus, "Count no man happy until the end is known".

------
joe_the_user
"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."

This is a great point. It has another corollary that people who are good X
approach aren't necessarily good judges of whether approach X is good. The
standard answer to "that seems like an excessively complex way to do it" is
generally "that because you don't have experience with doing it the right way"
and that could be right or it could be wrong. Often, the experienced and the
inexperienced have about equal chance to guess on the meta-level whether this
is true.

When OOP was the next big thing, a whole array of people defended against
objections with arguments around those not liking it "doing it wrong", which
we now, mostly, know were ridiculous right? Of course we know...

------
rtpg
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 just have a slightly
busted thing.

~~~
mgoetzke
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.

~~~
rtpg
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.

------
andyidsinga
I've worked with academics over the years - people who are much smarter than
me.

During that time, I've heard on more than one occasion a phrase that goes
something like this "a month in the lab saves an hour in the library".

My response, was usually quote the Car Talk guys "Reality often astonishes
theory"

The irony, and subject of endless entertaining remarks on the show was that
Tom Magliozzi had a PhD.

------
monktastic1
I'm reminded of the coastline paradox.

[https://en.wikipedia.org/wiki/Coastline_paradox](https://en.wikipedia.org/wiki/Coastline_paradox)

"The coastline paradox is the counterintuitive observation that the coastline
of a landmass does not have a well-defined length. This results from the
fractal-like properties of coastlines."

------
tw1010
People are surprisingly unimaginative about the richness of reality.

------
aj7
One thing I’velearned is that a bad design becomes more complex as you
progress through it. Sometimes, the complexity grows to eventually make the
whole design unfeasible, and you have to abandon it.

In rare moments, designs become simpler as you progress. Irrelevant or
neurotic features seem to melt away. That is bliss!

------
tmalsburg2
Great essay. Basically, they say that surprise doesn't tell us so much about
the world but more about our model of the world. The degree of surprise can
essentially be seen as a measure of our ignorance about some aspect of the
world. As such surprise can serve as a guide for improving our understanding.
However, it would be a mistake to see ignorance necessarily as a shortcoming.
A simplifying model of the world is preferable if it gets the job done. In
contrast to that, a perfectly accurate model of the world would render
decision-making computationally intractable and is therefore not desirable.

------
lamename
Excellent points and very true to my experience. I like this. I like it so
much I'm wary of it being the last word. Accounting for details & getting
perspective elsewhere is incredibly important for solving problems.

But with details alone in mind it's easy to fall into the trap of "there must
be 1 _more_ detail I'm missing" ad infinitum.

 _If you do anything where you have to solve problems in a fixed period of
time, it 's important to decide when to pivot to a new, more productive
problem_ (depending on the scale of your problem and freedom to change).

Take this advice or learn it the hard way.

------
hashkb
> 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.

I disagree. With physical objects there is elbow grease; a reality mistake on
the level of a typo is minor compared to a programming typo which is as good
as having no program written at all.

------
SubiculumCode
Tieing knots. A lot more to it than diagrams suggest, if only because the
hands have to learn the complicated movements while maintaining grip.

------
paraschopra
This actually has parallels to how I recommend finding startup ideas:
observing the reality and noticing anomalies and surprises. Here's my writeup:
[https://invertedpassion.com/to-get-good-startup-ideas-
look-f...](https://invertedpassion.com/to-get-good-startup-ideas-look-for-
anomalies/)

------
karmakaze
> The important details you haven’t noticed are invisible to you, and the
> details you have noticed seem completely obvious and you see right through
> them. This all makes makes it difficult to imagine how you could be missing
> something important

This. And how you could be pointing out something so self evident and it falls
on deaf ears.

------
Xeoncross
> I’ve mostly fixed it for myself. The direction for improvement is clear:
> seek detail you would not normally notice about the world.

> Reality has a surprising amount of detail

You can't have it both ways. The amount of details, relative to your ability
to perceive them all, is no-where near "mostly".

------
gwbas1c
I can't begin to count the number of times I've worked with an idea person who
can't comprehend the details; or a product manager who can't work through
high-level corner cases and expects that the computer can read his mind.

This is a good read for either of those kinds of people.

------
mirimir
Re boiling water in a metal pan: it's boiling when it stops making steam-
cavitation noise.

------
dekhn
The term we use at work is "Reality has fractal complexity".

------
amelius
So intuitively we have a tendency to make models of everything around us. And
now we are encouraged to smash those abstractions to pieces, so we can find
better ones. Does that sum it up?

~~~
tonyarkles
From a software perspective at least, my rule has always been "know that what
you're looking at is an abstraction, and know that there's details
underneath". Most of the time you can get by using the abstraction (e.g.
walking up and down the stairs), but once in a while you're going to have to
peel the abstraction back and look a bit deeper to understand what's going on
(e.g. replacing a cracked stringer).

I personally took this to an extreme... I learned to program at quite a young
age, and dual-majored in EE and CS specifically so that I could understand the
systems that ran my software. I'm happy writing Python, but if I need to dig
into the CPython run-time to figure out a bug I'm ok with that. And if I need
to run tcpdump to figure out why a TCP stream is stalling, I'm good with that.
The abstractions are beautiful and work 99.9% of the time, but if you don't
know how the abstractions are built, you're going to have a hard time figuring
out what's wrong when they break down.

------
vinceguidry
My answer to this problem is the same as it always was. Put it down, go take a
walk. Come back with a fresh mind. The brain evolved to do this. Engineering
is older than the human race.

------
drdrey
Everything is fractal. The more you zoom in on a detail, the more details
appear. Therefore it is impossible to get anything done, there is always
something to do beforehand

------
gtallen1187
This was a great read, thank you!

------
RMGgondella
Brilliant AF.

One of the hardest things to do is make difficult processes and systems
accessible. This article achieves that with a simple discussion of building a
staircase (no mean feat, first time) to step up to the springboard for a much
larger idea. It's almost as if observing the staircase details renders a
scaleable model fractal that gets to measurement of a learning curve.

I wonder if, by observing the details of one's own most difficult task,
focusing on the time to learn each detail and assemble one's own model, an
overall speed for learning ANY difficult task, done by a particular person
could be calculated. That could be a valuable tool for measuring human
potential, particularly in apprentice-type learning.

The value of the time and the effort put into the apprenticeship -- to both
the apprentice and the master craftsman -- could be assessed before hand.
Achievement baselines could be set closer to reality; or it could be decided
that the apprenticeship would not be worth the time and effort. But that last
decision could be made on firmer ground, data-wise.

Da Vinci, I would suggest, was a great observer of detail; he was also pretty
good at math, science, engineering, and architecture. But it all started with
drawing -- observing the most minute of detail, in all it's imperfection, then
transferring that to paper. As an artist, he also learned to sort of
standardize many of the imperfections -- or at least the use of the tool to
represent those imperfections on paper or canvas. The painting method he
galvanized, sfumato, eschewed hard lines in nature, and worked hard to achieve
the soft edge. I wonder if da Vinci saw the irrationality of pi as evidence
that a circle has no true "edge," but that a circle was instead equidistant
points stretching out in a small infinity, particular to a specif object

The downside of observation might be wrapped up in this last, though. Because
the casual observer of a circle, presuming that there is a definite, finite
edge to a circle could lose their faith in the dimensional space we've grown
up perceiving (four dimensions.) This might be okay for a mathematician, a
scientist, or an artist. To a suburban husband with a mortgage and a minivan,
it might be terrifying. The observation might completely unmoor him, and send
him drifting off.

Nature is like that. The infinite diversity of nature, at say, the class,
order, genus, species, or individual level can be maddening to try to take in.
Looking above, at "animal, mineral, vegetable" compounds that exponentially.
How those pieces work together to build a staircase, or a giraffe, or a seam
of granite, or the savanna of Africa, is the heart of scientific -- and
artistic -- inquiry.

Thanks, John Salvatier, for a provocative and insightful article.

------
Jedi72
TL:DR; Hofstadter's law.

~~~
KineticLensman
Hofstadter's law [0]: It always takes longer than you expect, even when you
take into account Hofstadter's Law.

Interesting, Hofstadter's original motivation for the law was the observation
(published in 1979) about the then delays in computers beating grandmasters at
chess (first in 1997 and now routinely_. This gives us a data point about
'just how long' things can take (in addition to the numerous examples from
software projects). Nuclear fusion is still out there...

[0]
[https://en.wikipedia.org/wiki/Hofstadter%27s_law](https://en.wikipedia.org/wiki/Hofstadter%27s_law)

------
Toast_25
TLDR: The curse of knowledge.

------
brndnmtthws
I've always thought the whole idea of virtual reality is strange. Why would I
want to experience the world through VR when I can experience reality instead?
I suppose there are exceptions where it makes sense. Maybe if someone is
physically incapable of having an experience, or the risk is too high, but for
the most part I derive more joy from actually going outside and doing stuff
than playing a video game equivalent.

To each their own, as they say.

By the way: great post.

~~~
LeifCarrotson
> physically incapable of having an experience, or the risk is too high, but
> for the most part I derive more joy from actually going outside and doing
> stuff than playing a video game equivalent.

Or financially incapable of having the experience, or time constrained - and
everyone is mortal and therefore time constrained.

I don't anticipate using VR to experience a walk in the local park, or
(personally) mountain biking on the local singletrack because those are things
I can do in real life with much more fidelity and have a much better
experience. However, I could understand taking a walk in a park on another
continent (or six other continents in one afternoon), or advising a friend
whom I've raved about mountain biking to try the trail in VR before buying
expensive equipment.

I'd rather have a compromise of some vast array of experiences across the
world in low-detail VR, and also enjoy the limited amount of experiences I can
enjoy in real life in full resolution, than to constrain myself to the small
slice of the world that I can afford to physically experience.

