
Mental Models I Find Repeatedly Useful - orph
https://medium.com/@yegg/mental-models-i-find-repeatedly-useful-936f1cc405d
======
mikekchar
Interestingly, I find my favourite nitpick: Ockam's razor. The article quotes
it as "The simplest solution is usually the correct one". This is a common
misinterpretation of it and it's interesting that the quote links to the
wikipedia page that has a better statement: "Among competing hypotheses, the
one with the fewest assumptions should be selected."

The key problem is equating simplicity with correctness. This is usually
disastrous. Once you feel that something is "correct" you stop looking for
ways to falsify it. That's the exact opposite for what Occam's razor is used
for.

Instead, if you have 2 competing hypotheses (two hypotheses for which the
evidence supports both), you use the one with less assumptions. Partly because
the one with less assumptions will be easier to work with and lead to models
that are easier to understand. But mostly because less assumptions makes it
easier to falsify.

Abusing this principle outside of the scientific method leads to all sorts of
incredibly bad logic.

~~~
scoot
My conclusion on reading this discussion is that if a bunch of smart people
can't agree on what Occam's razor is useful for, it isn't useful!

~~~
Lordarminius
>> drzaiusapelord ,scoot

Occams razor does not ask that you accept the simplest explanation. It asks
that one take into account as many, and only as many factors as necessary to
explain a phenom. It does not promote fallacy or lessen rigour. It is a "loose
leash but a tight chain"

As originally defined, it stated: Entities should not be multiplied without
necessity(Entia non sunt multiplicanda praeter necessitatem).

Bertrand Russel held the principle in high regard. This quote from Newton
encapsulates its application: "We are to admit no more causes of natural
things than such as are both true and sufficient to explain their
appearances." and simplified for scientists in this form: ""when you have two
competing theories that make exactly the same predictions, the simpler one is
the better"
[http://math.ucr.edu/home/baez/physics/General/occam.html](http://math.ucr.edu/home/baez/physics/General/occam.html)

There is a line of scholarship that believes William of Occam (c1287-1347)
never made the quote attributed to him.
[http://www.logicmuseum.com/authors/other/mythofockham.htm](http://www.logicmuseum.com/authors/other/mythofockham.htm)

What is termed Occams razor by vog asQuirrel asmad and others is a
statistical/logicians derivative not really of concern to most people.

------
btilly
Two adjustments that I would make.

Remove Metcalfe's law. It is a massive overestimate. See
[http://www.dtc.umn.edu/~odlyzko/doc/metcalfe.pdf](http://www.dtc.umn.edu/~odlyzko/doc/metcalfe.pdf)
for the better n log(n) rule for valuing a network.

And I find Le Châtelier's principle generally applicable, and not just to
Chemistry. It says that if you observe a system at equilibrium, and try to
induce a change, forces will arise that push it back towards the original
equilibrium. It is one thing to recognize this at work in a chemical reaction.
It is quite another to be blindsided by it in an organization.

See [http://bentilly.blogspot.com/2010/05/le-chateliers-
principle...](http://bentilly.blogspot.com/2010/05/le-chateliers-principle-
not-just-for.html) for my explanation of why this holds in general outside of
chemistry.

~~~
philh
One thing I question with Le Châtelier, is how do you know which equilibrium
will be pushed back towards?

Humans have a desire pro-speed and anti-risk. Supposedly, if you introduce
seatbelt laws, speed increases and risk stays the same. How do you predict
that in advance? Why doesn't risk decrease and speed stay the same? Or why not
speed increase a bit and risk decrease a bit?

~~~
btilly
Push it back towards does not mean that it necessarily arrives at its original
position. Just that it didn't wind up as far away from it as you'd naively
hope.

------
uola
Ugh, maybe I'm the only one but I don't find this list useful. Not because it
isn't interesting, but the implication that it will actually make you smarter.
The problem today isn't information, it's knowledge. Even if you can correctly
and fully understand all these models, something that could take years, you
still most likely wouldn't be able to implement them, especially when they are
in conflict with each other.

I think it's a much better idea to study things like critical thinking,
practical reasoning and operational leadership. Back in the day hacker values
stated that you could ask for directions, but not for the answer. Because the
process itself was as important as the answer. Not just for amusement, but
because there might not be a right answer and the next time you're confronted
with a similar problem you now have some experience of making those decisions.

A great deal of "stupidity" in technology these days seem to stem from schools
that promote check box answers to complex problems and the popularity of these
"laws" that make people so sure of themselves that it prevents them from
proper reasoning.

~~~
adrusi
This list is useful for people who are already used to thinking in these ways,
intuitively, by being exposed to other people and learning by osmosis.
Formalizing intuition leads to easy growth.

For other people, you're right, it's about as useful as reading through a list
of course descriptions rather than taking the actual courses.

~~~
uola
"This list is useful for people who are already used to thinking in these
ways, intuitively, by being exposed to other people and learning by osmosis.
Formalizing intuition leads to easy growth."

That's exactly what I'm questioning though, if that's the right way to learn
things. Especially with the premise of the article, there's a risk that people
are just "collecting facts" to be used as anecdotes to avoid reasoning.

"For other people, you're right, it's about as useful as reading through a
list of course descriptions rather than taking the actual courses."

Somewhat ironic I read course curriculums all the time to figure out which
subjects are covered and what are good beginner books.

~~~
mwfunk
I think everything on this page is about encouraging reasoning rather than
just collecting facts. If someone takes each one as a truism and blindly
follows it, then yes, it would turn these mechanisms (which are supposed to
help us identify and fight our own cognitive biases) into just another form of
cognitive bias. That's why they're not laws, they're just handy patterns to
help us reason about things that we see every day.

I'm not sure what you mean by using them as tools to avoid reasoning- they are
explicitly meant to help with reasoning. I don't know what sort of reasoning
could be done without incorporating any sort of logical frameworks at all.
That's all this stuff is, tools to aid reasoning by identifying common
patterns and antipatterns in thoughts and perceptions about the world around
us. Anyone who treats these ideas as absolute laws rather than occasionally
(frequently) useful abstractions is doing it wrong.

~~~
uola
"That's all this stuff is, tools to aid reasoning by identifying common
patterns and antipatterns in thoughts and perceptions about the world around
us."

Identifying patterns is second to learning something. Logical fallacies are
examples of bad arguments. You should first learn how to evaluate an argument
[0] before trying to identify logical fallacies. Not only will you learn more,
but there's a greater chance you will be able to put any given "model" in
context. That people find things like logical fallacies useful is an
indication that they don't understand the fundamentals.

[0]
[https://www.google.com/search?q=critical+thinking+argument+e...](https://www.google.com/search?q=critical+thinking+argument+evaluation)

------
sitkack
This is super useful, I have a similar list but it also includes techniques
and ideas

    
    
      * Dimensionality Reducing Transforms
      * Hysteresis, Feedback
      * Transform, Op, Transform
      * Orthogonalization for things that are actually dependent
      * Ratios, remove units, make things dimensionless
    

A big one, that helps me immensely, is that when I need to do a
big/risky/complex task, is to imagine myself doing with with sped up time.
Instantly creates an outline and list of tools that one will need.

~~~
gbhn
Can you write more about "sped up time"? I'm reminded of something like this:
[http://lesswrong.com/lw/mnp/travel_through_time_to_increase_...](http://lesswrong.com/lw/mnp/travel_through_time_to_increase_your_effectiveness/)

~~~
sitkack
This is more metaphysical than the basic technique. If I was going to exchange
the hard drive in my laptop. I would visualize the entire process, noting the
questions and problems as I completed each step.

    
    
      * do I have the proper tools? Lookup special fasteners
      * I will misplace the screws, a magnet or plastic cups would help
      * It might be dirty inside, I need something to clean 
      * I might drop a screw inside, tweezers
      * Could be dark, headlamp
      * cable might not stay in place, tape
    

It might take 20-30 seconds to run through all the steps in ones mind,
anticipating problems before they arise.

------
rwallace
Good list! A few suggested tweaks:

Veblen goods clearly exist, but the evidence for the existence of Giffen goods
is much more suspect. (Did the poor really eat more bread because the price of
bread rose, or because there was an across-the-board increase in the price of
all kinds of food?)

The Precautionary Principle is not just dangerous or harmful, but guaranteed
suicide; as things stand right now, we are all under a death sentence. It
needs to be replaced by the Proactionary Principle, which recognizes that we
need to keep making progress and putting on the brakes is something that needs
to be justified by evidence.

Any list that has sections for both business and programming needs some entry
for the very common fallacy that you can get more done by working more hours;
in reality, you get less done in a sixty-hour week than a forty-hour one.
(Maybe more in the first such week, but the balance goes negative after that.)

The distinction between fixed and growth mindset is well and good as far as it
goes, but when we encourage the latter, we need to beware of the fallacious
version that assumes we can conjure a market into existence by our own
efforts. You can't become a movie star or an astronaut no matter how hard you
try, not because you lack innate talent, but because the market for those jobs
is much smaller than the number of people who want to do them.

------
source99
A technique I often use to test a theory is to change the inputs to be the
maximum and minimum possible values and see if the model still holds true.
I've found it to be incredibly useful in a few specific situations.

~~~
mistermann
I've always thought this _should_ be a very effective way to explain a point
to someone, but in practice it rarely seems to work....maybe that saying
applies, something about you can't use logic to change the mind of someone
that didn't use logic to arrive at their conclusion.

~~~
rwallace
That might be because you're trying to use it to argue politics, where it's
less applicable; hard cases often make bad law, and you can easily end up with
a straw man. It works better in science and engineering.

------
erikb
I think pg also wrote an essay about a mental model that I find interesting:
When in doubt, it's probably not about you.

There are many events that we usually think are related to us, but actually
aren't, like your boss or customer being angry is in most cases not about you
but something else.

I have looked through a lot of pg's essays but didn't find it. He probably
removed it just that I can't find it (/example).

If someone else finds it, please link.

~~~
arviewer
When shop personel is not friendly, we tend to think that that person is not a
friendly person, as a character trait. When I'm not friendly in the same
situation, it's because I didn't get enough sleep, or because I had a fight
with my girlfriend that morning. So in my case it's circumstantial, temporary,
not my fault, in the other person's case it's the person's fault and
permanent.

What you describe is our inner voice doing the same thing. (This is my
personal explanation!)

Google for "inner voice doubt" and find out more!

~~~
rwallace
Yes. For another search term, the fallacy in question is sometimes called the
Fundamental Attribution Error.

------
csallen
I'm surprised he rates cost-benefit analyses as a 2 ("occasionally" used)
rather than a 1 ("frequently" used). Making good decisions almost always
requires taking a hard look at both the costs and the benefits. It cannot be
overstated how often bad decisions are made because the parties involved
simply neglected to factor in the costs (including opportunity costs).

I personally use cost-benefit analyses for every non-trivial decision in my
life.

~~~
BurningFrog
Yeah, the "X has a benefit, so we should do X" fallacy is really common, both
in software development, politics, and most everywhere.

------
delish
Some commenters here are saying, "I already know this stuff." Indeed. I'd be
curious if people could put out a list of "advanced" mental models. For
example, Bayes' theorem is more advanced than Occam's razor.

What's clearly more advanced than Bayes' theorem, and as useful? ET Jaynes'
flavor of probability theory? I'd posit the more advanced version of active
listening as, "being able to perform a bunch of kinds of therapy--freudian,
rogerian, family and systems etc." Of course I don't mean you go get a license
for these things. I'm positing them as difficult, generally-applicable life
skills. I'm not claiming these are good examples; I think HN can come up with
better ones.

~~~
VLM
Thinking being a flux of information, and EE telecom theory having discovered
all kinds of laws about flow of information, its no surprised that those
models apply pretty well to the engineering tradeoffs of general mental models
of thinking or thinking about information in other contexts.

EE control theory class IS an entire senior year class on applying a model to
something (a thermostat?) which isn't terribly hard, and then modeling and
measuring its performance and finally optimizing the model which is pretty
hard.

Shannons law explains how good ideas, noise/distraction/bad ideas, depth of
concentration or maybe total volume of information, and rate of mistakes all
interrelate and how changing one (or several) will affect the others in
general.

There are some interesting tradeoffs in communication filter design (analog
hardware or modeled in DSP) along the lines of you can freely trade smoothness
in response (group delay, ripple, latency, monotonicity kinda), accuracy in
response, and complexity/cost. These tradeoffs apply to everything in the
world that processes things not just filter synthesis.

There is some kind of chaos theory "thing" where as feedback mechanisms become
more complicated, oscillation becomes inevitable and unpredictable. Doesn't
matter if we're talking about high gain amplifier design or world economic
models.

This is aside from the general engineering mental models of a good engineer
can freely exchange cost, reliability/safety, and performance. In fact it
being enormously easier to exchange in those rather than expand, you can
pretty much see thru transparent marketing that only mentions one or some
factors. This applies to all of reality not mere structural engineering.

I think the optics people could say a lot about their seemingly endless stable
of aberrations. There are so many effects and interactions its surprising
anything optical works at all, much less works well. Optics is almost a meta
law that everything interacts with everything and constants aren't.

------
RickHull
I'm just getting exposed to this line of thinking and find it fascinating.
Another resource I found recently was
[https://www.farnamstreetblog.com/mental-
models/](https://www.farnamstreetblog.com/mental-models/)

 _Disclaimer: I 'm not sure if it's derivative blogspam or legitimately
insightful / original_

------
agorabinary
A nice metacognitive cheat sheet.

Missing a couple interrelated mental models I find very important:

\- emergence: a process whereby larger entities, patterns, and regularities
arise through interactions among smaller or simpler entities that themselves
do not exhibit such properties

\- decentralized system: a system in which lower level components operate on
local information to accomplish global goals

\- spontaneous order: the spontaneous emergence of order out of seeming chaos.
The evolution of life on Earth, language, crystal structure, the Internet and
a free market economy have all been proposed as examples of systems which
evolved through spontaneous order.

------
LeicesterCity
Could someone give me a real example of somebody using mental models in a real
world application? I just find the idea of learning and studying mental models
to be distracting and confusing. Pardon my ignorance.

~~~
scarecrowbob
To be honest, I think that the process is something like:

I struggle with problems and eventually find a solution,

I encounter a name for a similar solution,

as I encounter new, similar problems, I begin to recognize "how the model
works",

I forget about the model when I don't use it,

occasionally I come across a list like this one where it's fun becasue it
validates the usefulness of the models I've already found and introduces me to
new names for ones I already have encountered.

I don't feel that a list like this is super useful to me outside of that
framework-- I wouldn't take it as a "study guide".

But I feel that framework has given me a lot of personal validation and
pointers on how to better deal with problems I encounter.

------
agentgt
I still think Social Psychology was one of the most useful classes I ever took
in college. Sure some if it is probably dated by now but the cognitive biases
theories really helped me further in life.

I remember telling some class mates to take the class and they assumed it was
for an easy A and not for how useful the class would be (and I went to a
GaTech a long time ago and well the social sciences were just not respected
like engineering disciplines at the time).

~~~
qubitcoder
As a fellow Georgia Tech grad, I wholeheartedly concur. The course on
Political Philosophy was not only one of the most challenging classes, but
also the most useful in daily life. It really changed how I think about the
world--so much so that I decided to to double major in international
affairs/modern languages. It's a pity that the social sciences/liberal arts
aren't as respected at engineering schools. Those courses were equally
enriching (if not more so) to my life as combinatorics, differential
equations, and quantum mechanics.

------
adamnemecek
To the development section, I would add the concept of computational
context/state, caching, and queue/event loop.

This HN comment summarizes it pretty nicely "everything in an OS is either a
cache or a queue"
[https://news.ycombinator.com/item?id=11655472](https://news.ycombinator.com/item?id=11655472)

Also Overton window

------
karmacondon
I have a similar list of useful concepts. My goal so far this year was to
expose myself to those concepts as often as possible. I made an app for my
phone that displays the concept of the day on my home screen (right now it's
the rhetorical concept of periodic sentences). I also made images for each of
the concepts that I use as my chromecast backdrop. I've seen each of them
dozens of times by now, mostly unconsciously.

So far, mixed results. I would like to say that I think of "Bayes Theorem" at
the perfect time because I wrote it on a list, but that never happens. I guess
I've benefitted from thinking about these concepts more, but that's almost
impossible to measure. A list of 100 useful mental models has limited value if
you can't hold all of them in memory at once and retrieve them at the right
time. I'm still trying to come up with a solution for this. Unfortunately I
think this might be a fundamental limitation of human learning.

~~~
peteretep
Instead, try and think of a situation in the previous day when you might have
applied it, and imagine applying it to a problem in the coming day.

------
Double_Cast
> _What am I missing?_

In planning a strategy, I've found it helpful to consider _Win Conditions_. It
forces me to think backwards from the goal, construct a dependency tree, and
consider resource allocation. I first heard about it from videogames but I've
also seen it in math, engineering, logistics, recipes, etc. I also pattern-
match it the insight that solved the _Problem Of Points_ [0] which motivated
Probability Theory. If it were on the curated list, I'd expected to find it
under "models" next to cost-benefit analysis.

[0]
[https://en.wikipedia.org/wiki/Problem_of_points#Pascal_and_F...](https://en.wikipedia.org/wiki/Problem_of_points#Pascal_and_Fermat)

------
frankus
Great list, although I prefer the term "thought technology" (as coined by John
Roderick) to "mental model".

~~~
dredmorbius
So, a question back at you. Let's suppose an ontology of technological
_mechanisms_. That is, describing technologies by _how they operate_. I've
kicked some ideas around and come up with:

1\. Process-knowledge. Arts and practical stuff, say, agriculture,
construction, boatbuilding, sailing, etc.

2\. Fuels & combustion, generally. Wood, plant and animal oils, charcoal,
coal, petroleum, steam, otto, deisel, turbine engines.

3\. Materials. Functions dependent on specific properties, and abundance of
materials they're based on.

4\. Power and transmission.

5\. Sensing, perception, symbolic representation & manipulation.

6\. Systematic knowledge. Science, geography, history.

7\. Governance, management, business, & institutions.

8\. Scaling and network technologies. Cities, transport, communications,
computers.

9\. Sinks & unintended consequences. Pollution, effluvia, systems disruption,
and their management.

"Thought technology" probably falls into scientific knowledge (models) or
symbolic processing.

Thoughts?

More: [https://ello.co/dredmorbius/post/klsjjjzzl9plqxz-
ms8nww](https://ello.co/dredmorbius/post/klsjjjzzl9plqxz-ms8nww)

------
shunyaloop
On-going series on mental models at
[http://www.safalniveshak.com/category/mental-
models/](http://www.safalniveshak.com/category/mental-models/)

------
ternaryoperator
His definition of a "strawman" is incomplete. It's not simply misrepresenting
someone's argument, it's misrepresenting it specifically by analogizing it
falsely to something similar that is easier to attack. The example he links to
is a rather exaggerated strawman. I think most people would favor the strawman
explanation in Wikipedia[1]

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

~~~
lerpa
Many of his definitions are incomplete.

------
k__
The wrong assumption about Ockams Razor is probably the cause of so many
people re-inventing the wheel.

"I don't need this big framework, I can do with much less!"

------
votr
How would one actually use this stuff?

~~~
learc83
This is one of those lists that would be completely unhelpful if you don't
already know how to use most of what's on the list.

~~~
kelukelugames
Agreed. It's as helpful as the other post on list of free online programming
books. Needs more handholding to help people make the best use of the list.

------
mizzao
This book is a very handy pocket reference that overlaps with many of the
ideas mentioned here:

[https://www.amazon.com/Decision-Book-Models-Strategic-
Thinki...](https://www.amazon.com/Decision-Book-Models-Strategic-
Thinking/dp/0393079619)

------
ElijahLynn
This is the core of the book Peak: Secrets from the New Science of Expertise.
It is a book of how to create a mental representation of what successful
mental representations look like.

The most successful people, peak performers are those who have the best mental
representations.

------
Lordarminius
I would add to the list 'revealed preference'

'... an economic theory of consumption behavior which asserts that the best
way to measure consumer preferences is to observe their purchasing behavior.
Revealed preference theory works on the assumption that consumers have
considered a set of alternatives before making a purchasing decision. Thus,
given that a consumer chooses one option out of the set, this option must be
the preferred option' [http://www.investopedia.com/terms/r/revealed-
preference.asp](http://www.investopedia.com/terms/r/revealed-preference.asp)

In other words "observe their actions, not their words"

------
ForHackernews
Are these "mental models" or just a bunch of clichés / pithy aphorisms? To me,
a mental model would be something more like "visualizing possible state
transitions as a directed graph" or something like that.

------
preordained
Nice. They got Hick's law...that's one of my favorites, not so much in
development, but sports. I train Brazilian jiu-jitsu, and I find substantial
improvement in my reaction time by having only 2-3 well-worn options at my
disposal (even 3 starts to feel crowded) in an given position, rather than a
multitude of counters/attacks. When someone is trying to strangle you, go left
or right is often a better choice than let's-check-the-mental-database-for-
the-ultimate-move.

------
jtlien1
The mental model from economics that is widely misinterpreted is comparative
advantage. Most think it means you/a country etc should specialize in that
which you are best at. And then free trade will work to your advantage. But it
actually means that even if you are worse at producing products A and B than
another country, if your ratio of A/B is better than the other country, it
would be good for you to produce A and trade it to the other country for B
etc. I

------
rdlecler1
A couple more:

Evolution

> Frequency-dependent selection: fitness of a phenotype depends on its
> frequency relative to other phenotypes

> Evolutionarily stable strategy (ESS) is a strategy which, if adopted by a
> population in a given environment, cannot be invaded by any alternative
> strategy that is initially rare. It is relevant in game theory, behavioural
> ecology, and evolutionary psychology. Related to Nash Equilibrium and the
> Prisoners dilemma.

Economics

> Debasement (gold coins): lowering the intrinsic value by diluting it with an
> inferior metal.

------
barrystaes
Quite a few of these "mental models" are just a definition of terminology like
"botnet". Come to think of it, the complete list is just definitions..

------
agentgt
I would say "Divide and Conquer" should be a 0... it is that useful and it can
be applied to many many different categories.

So many things seem intractable and formidable in complexity yet once these
things are broken down into pieces things become clear. The Asana CEO once
talked about this. Breaking things out provides clarity and once you have
clarity productivity is massively increased.

------
projectileboy
If you enjoy these sort of summaries, I encourage you to check out the book
"Seeking Wisdom" by Peter Bevelin [https://www.amazon.com/Seeking-Wisdom-
Darwin-Munger-3rd/dp/1...](https://www.amazon.com/Seeking-Wisdom-Darwin-
Munger-3rd/dp/1578644283)

------
steveeq1
There is also an app from the apple app store that has most of these mental
models in book form: [https://itunes.apple.com/us/book/think-mental-
models/id61236...](https://itunes.apple.com/us/book/think-mental-
models/id612365806?mt=11)

------
philip1209
I thoroughly enjoyed the book Inside The Box, which presents four mental
models for creative problem solving. The core idea that creating rules can
help creativity is a pattern toward which I think most technical people
(including myself) feel averse, but actually can be beneficial when studied
with an open mind.

------
galfarragem
I recurrently use: _Everything is a_... [1]

Even when this model doesn't explain 100% of occurrences is great as a
starting point of view to understand the main pattern of a complex system.

[1] -
[http://c2.com/cgi/wiki?EverythingIsa](http://c2.com/cgi/wiki?EverythingIsa)

------
vetras
Perfect, but how do you use these models?

Are you supposed to know all 100's of them by heart and then, in the middle of
conversation, go: "Ah, but X principle says Y, therefore we will go with Z
option". Is it? Am I missing something?

I mean, I'd love to use this but I don't have enough brain cells for all of
those :)

------
misterdata
I'd add Amdahl's Law [1], which is about the relationship between adding
resources for executing a task, and the speed-up that delivers.

[1]
[https://en.wikipedia.org/wiki/Amdahl%27s_law](https://en.wikipedia.org/wiki/Amdahl%27s_law)

------
cvwright
It's an interesting list. Though I'm a bit baffled at why he has Power-law as
a "1" (comes up frequently) and Heavy-tailed distribution as a "3" (rarely
comes up). A power law _is_ a heavy-tailed distribution!

------
RivieraKid
Very underwhelming, I'm actually quite surprised that most people seem to find
this useful and interesting. I mean, normal distribution, Moore's law, minimum
viable product, paradox of choice... that's pretty basic stuff.

------
bootload
under competing, I'd add OODA loops ~
[https://en.wikipedia.org/wiki/OODA_loop](https://en.wikipedia.org/wiki/OODA_loop)

~~~
seizethecheese
Specifically the competitive aspect of getting inside an adversary's OODA loop

------
quadrangle
Along with the reference to Arrow's Impossibility Theorem, I'd want a
reference to the fact that voting can be done in ways other than ranking, e.g.
approval or score voting.

Overall, a superb list.

------
jacquesm
Nice list! I really miss this one:

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

------
known
[https://en.wikipedia.org/wiki/List_of_eponymous_laws](https://en.wikipedia.org/wiki/List_of_eponymous_laws)

------
dmisdm
Have a look at the Single Responsibility and High Cohesion principles, which i
think should be included in development/design

------
adamnemecek
Is Gabriel Weinberg related to Gerald Weinberg? No right? I've been wondering
this for some time now.

------
xchip
An article that goes straight to the point. I like it!

------
criddell
Inflation is a mental model? Peak oil? Botnet?

~~~
jmmcd
I think these can be defended as mental models, even though the article
doesn't do a good job of it.

We're familiar with inflation in the financial sense. But then there is also
grade inflation. There is inflation of superlatives in our language, e.g.
"great" and "awesome". Once we see a few examples we realise that inflation is
a more general concept, and a useful one to use in explaining a lot of
situations.

Same for peak oil, I think. Not sure about botnet.

~~~
criddell
I went back to look at the article again and now see that he says almost
exactly what you just said. Was that there before?

~~~
jmmcd
Hmm.. the entry on inflation hasn't changed (doesn't say anything like what I
said) but I see notes that mention grade inflation. I don't know whether that
was there first time round.

------
bcherny
Nothing ground breaking here - I imagine most readers here already use most of
the author's models - but this is a nice comprehensive list, which I have not
seen before.

~~~
kough
Does anyone have a pointer to a list of these lists? Would be interesting to
know what models people use on a day-to-day basis, like usesthis.com for the
brain.

~~~
_yvjs
I've started keeping such a list actually: [redacted]

~~~
dredmorbius
Ah, that's the first actual pinboard page I've seen -- I've been looking
at/for archival tools for some time, currently Pocket.

~~~
_yvjs
I'd recommend it. I was grandfathered into the free plan but $11/year seems
fair.

Regardless of what you settle on I'd look for the equivalent of
[http://www.packal.org/workflow/alfred-
pinboard](http://www.packal.org/workflow/alfred-pinboard) for whatever service
and platform you use. Being able to instantly search through all fields of all
items in your archive is pretty great and has changed the way I work.

~~~
dredmorbius
Pocket has comprehensive search, which is pretty slick. The tagging feature
leaves much to be desired, though it's also far better than Readability.

------
fizixer
I guess what you described goes by a well-known term called 'critical
thinking'?

~~~
dredmorbius
Strictly no, though what's offered in part complements, in part substitutes,
for critical thinking. Some of these _are_ components of critical thinking (or
describe), much isn't.

This is a set of both guidelines and heuristics, a set of patterns, if you
will, which can be applied to situations or analyses. Some give you a fast
route to a simple answer (Occam's Razor), some give pause before accepting
what appear to be well-founded results (Simpson's Paradox -- I've encountered
that before but had largely forgotten it). Some are simply shortcuts in
estimation (order-of-magnitude, and log-based math -- multiplication and
division become addition and subtraction).

Critical thinking has varying definitions, but I'd generally describe it as
more structured and procedural than what's offered by @wegge. See:
[https://en.m.wikipedia.org/wiki/Critical_thinking](https://en.m.wikipedia.org/wiki/Critical_thinking)

------
newgrad
wow, this is really useful. thank you.

------
crimsonalucard
aka buzz words to make you sound more intelligent.

------
ucaetano
Interestingly, that's about 75% of my 2-year MBA.

Sure, it's far different doing daily training to get those concepts ingrained
in your mind so you don't have to actively think about them, but it's nice to
see them listed like this.

Here are a couple more:

\- Overconfidence bias: we usually think we're better than the average on
something we know how to do (driving) and worse than the average in something
we don't (juggling), even if almost nobody knows juggling and everyone knows
how to drive

\- No alpha (aka can't beat the market): you can only consistently beat the
market if you're far better at financial analysis than a lot of people who do
it every day all day. So don't bother trying.

\- Value chain vs. profits: you'll find that most of the excess profits in the
value chain of a product will be concentrated in the link that has the least
competition

\- Non-linearity of utility functions: the utility of item n of something is
smaller than item n-1. Also, the utility of losing $1 is smaller than (1/1000)
utility of losing 1000. This explains insurance and lotteries: using linear
utility function, both have a negative payout, but they make sense when the
utility function isn't linear

\- Bullwhip effect in supply chain: a small variation in one link of the
supply chain can cause massive impacts further up or down as those responsible
for each link overreact to the variation (also explains a lot of traffic jams)

\- Little's law: in supply chain (and a lot of other fields): number of units
in a system = arrival rate * time in the system

I'll add more as I think about them.

~~~
rsp1984
_\- No alpha (aka can 't beat the market): you can only consistently beat the
market if you're far better at financial analysis than a lot of people who do
it every day all day. So don't bother trying._

I'd argue that you can have alpha if you are better informed than everybody
else. Financial analysis is the craft that comes after that. So yes, if all
you have is financial analysis don't bother trying to beat the market. But if
you have some unique insight, some information that the market doesn't have or
doesn't see, then with some added financial analysis on top you do have an
advantage that you can use to generate alpha.

~~~
ucaetano
Sure, but insider trading is illegal. So let's say you can only rely on
publicly available info, which everyone else has.

Then "unique insight" is financial analysis, plus macroeconomic analysis, etc.

In other words, if everyone have access to the same info, you can only
consistently do better than the market by consistently having better analysis
than the market. Everyone is seeing the same info, so you don't do better by
seeing some piece of info others are not seeing, but by using different
weights in your analysis than the market is using.

And even in those cases, the market might stay irrational longer than you can
stay solvent.

~~~
rsp1984
You work with an oversimplifying model of reality.

Say you've worked in a specific industry for a long time and you know all the
players. You know where the technology is, what the challenges are and where
the tech is going. You know how key companies are managed, you have an idea
about their goals and strategies. You know who's best positioned for what's
coming. This is just general knowledge that you've acquired through your job
over the years. Now say you've made enough money and retire. Because you know
a thing or two about your industry you decide to buy or sell some stock. Can
this be called insider trading? Perhaps. Is it illegal? Most likely not. Can
you derive alpha from it? Hell yea.

~~~
ForHackernews
Why aren't you super rich, then? If that's really true, then go do that thing
you said.

~~~
your_ai_manager
Straw man

------
peterkshultz
If the 29 minute read time is intimidating, consider this link:
[https://www.farnamstreetblog.com/mental-
models/](https://www.farnamstreetblog.com/mental-models/)

All the information, easier to read quickly.

~~~
xiaoma
It was a nine minute read for me. Medium's estimates are always off and
especially so when dealing with list-type posts.

Instead of relying on how long some website says something will take to read,
it's usually a better idea to scroll through once just doing scanning at the
high level to get an idea of length and then read it if you want to.

------
hackaflocka
"Spamming" is a mental model? Mmmmmkay.

~~~
VladimirGolovin
Besides its original meaning (repeated uninvited bombardment with information
packages) I can think of only one alternative use of the pattern: games.

For example, rocket / grenade / arrow spam in TF2, or Lucio / Hanzo / Symmetra
projectile spam in Overwatch. In this context, spamming is just firing in the
general direction of the enemy, hoping that some of the rounds will hit.

Maybe this generalizes to repeated application of some cheap technique that
has a low probability of success, where the low chances of success are
compensated by the low amount of effort per 'shot' required -- but I can't
think of any more examples.

~~~
hackaflocka
That's pretty good. Gotta applaud you.

------
fatdog
TL;DR; What you learn in an Economics degree.

------
throwaway_1004
Such cynical words, besides depriving the world of a much needed listicle,
will also get us downvoted. Please don't offer such awkward comments which
might cause people to pause and think. Now back to my facebook feed..

~~~
dang
We detached this comment from
[https://news.ycombinator.com/item?id=12040892](https://news.ycombinator.com/item?id=12040892)
and marked it off-topic.

