
Ask HN: How can I “work-out” critical thinking skills as I age? - treyfitty
As I get older, I realized I’m not as sharp as I used to be. Maybe it’s from the fatigue of juggling 2 kids, but I’m very ill prepared for interviews because I simply can’t answer “product questions” and brain teasers. It’s a skill I need, and truthfully I was never good at consultant type questions to begin with but I’m seeing a lot of these questions in Data Science interviews.<p>Any help or resources will be tremendously appreciated.
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wenc
From the description, it sounds like what you're asking about is more along
the lines of mental acuity rather than critical thinking per se (the latter is
more about analysis in order to form judgments -- recognizing fallacies,
rhetoric, and using deductive/inductive logic to form arguments).

If you're asking about mental acuity so you can think faster and solve brain
teasers at interviews, many of the other comments in this thread offer great
suggestions. Achieving familiarity with the problem space and pure practice
are keys.

If you're asking about actual "critical thinking" (though I suspect that is
not the case from your description, but it's an interesting topic that you
might want to pursue anyway), the classic methods are the Socratic method,
disputation and critical discussion of ideas with other people. If you don't
have that luxury, you can train yourself by arguing with authors in the
margins when you read books. Writing is key -- it helps crystallize thoughts
and reveal weaknesses in thinking. Courses in philosophy also help provide a
foundation on different approaches to reasoning.

~~~
BOOSTERHIDROGEN
Any books about this ? Thanks

~~~
wenc
Try this [https://www.amazon.com/Critical-Thinking-Brooke-Noel-
Moore/d...](https://www.amazon.com/Critical-Thinking-Brooke-Noel-
Moore/dp/0078119146)

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rtkaratekid
I’m surprised no one has mentioned, but cardiovascular exercise is the number
one know method to improve the health and function of your brain. Other
suggestions are great as well if used in conjunction. I’ll come back and edit
this with sources when I get the time.

~~~
giantg2
I upvoted this but want to add that a good a diet is also a strong component.
Exercise will not make much of an impact if one is eating tons of transfats,
excessively drinking, abusing many drugs, etc. Mental and emotional health
make a difference too. Prolonged periods of depression change the
physiological and anatomical aspects of the brain.

~~~
rtkaratekid
Oh that’s a great point. Maybe it would be even better to have a somewhat
blanket idea of taking care of yourself physically.

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mkbkn
I may get downvoted for this but do check your Vitamin D3 and Vitamin B12
levels.

~~~
enchiridion
Is this in some way controversial? Seems like good advice.

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jorangreef
Play chess, and do physical exercise.

Both will develop your mental stamina, and chess especially will hone your
adversarial thinking.

You may even find that your chess fitness is directly comparable to your
programming fitness and vice-versa. When you're programming fit through
working on some incredibly hard problems in the week (think distributed
systems or file systems or algorithms), then your chess will show an
improvement. And when you're playing several hours of chess a day against a
good opponent, then your programming will likewise benefit and your bug count
drop as you naturally start thinking further ahead.

~~~
arsenide
I recommend go instead of chess, for the same reasons.

I played chess for years, learned go, and haven’t looked back. I personally
prefer it.

YMMV

~~~
jesterson
Pardon me for a stupid question, but you're not referring to go-language, are
you?

~~~
arsenide
Nope! The game! Though I think learning other programming languages through
toy projects is useful, that’s a separate opinion

~~~
maps7
Do you have a favoured online site?

~~~
arsenide
I play mostly on the Asian servers (Tygem and Fox Weiqi) because it is very
fast to get games. For beginners and players ranked up to about 10kyu I
recommend online-go.com! The Asian servers mentioned are also good for
beginners, just not as easy to get into

------
edimaudo
It will be a combination of things. Make sure you are getting enough sleep and
exercise. Pretty mind boggling that they are still asking brain teasers in
interviews. If that is the type of question they are asking you can practice
brain teaser and consulting type questions before an interview to. Have a good
grasp of the fundamentals of any subject matter before an interview. Practice
is key.

Outside of that apply the concept of katas daily
([http://codekata.com](http://codekata.com))

------
rmrfstar
For Data Science brain teasers, solving math problems that require clever use
of the fundamentals. That means calculus, linear algebra, and basic stats.

A ninja is not defined by his sword. Reading books gives you new weapons, but
you must learn to use them proficiently. Solving problems is therefore
critical.

Some good sources of problems:

Sanjoy Mahajan (2010) "Street Fighting Mathematics"

Xingfeng Zhou (2008) "A Practical Guide to Quantitative Finance Interviews"

Timothy Crack (2019) "Heard on The Street: Quantitative Questions from Wall
Street Job Interviews"

~~~
mindentropy
What do you recommend for data structure and algo interviews to keep the brain
sharp?

~~~
hackermailman
Competitive Programming
[https://cpbook.net/#CP4content](https://cpbook.net/#CP4content)

Kattis online judge you can use many languages
[https://open.kattis.com/help](https://open.kattis.com/help)

------
mguerville
I stumbled onto brilliant.org recently and while it’s a bit narrow (Math
skills), it seems better suited to cognitive training than most other attempts
I’ve seen

------
muzani
Reading definitely helps a lot. Pick up different types of books, such as
entomology, city planning, history, marathon training. Even beginner level is
good enough. You just want to see how people solve problems.

------
m0zg
Thinking in general is greatly affected by two things:

1\. Physical exercise. Some blend of cardio and strength training is
preferable, but at least cardio is pretty much a requirement.

2\. Sleep quality. Not just duration, but quality as well. If you have sleep
apnea especially (many people do and don't even know it), you need to address
that.

Also, if you're getting _interviewed_ in such detail as a consultant, you're
playing the consulting game wrong. People should just hire you based on your
track record as exemplified by direct recommendations from previous customers
and people within your network.

One of the benefits of a consultant from a customer standpoint is that if they
determine they've made a mistake, they can just terminate your contract. So an
elaborate interview is a waste of time for both sides.

------
brudgers
I'm not sure you can if the definition of "critical thinking" is forming snap
solutions to novel problems in a few minutes. Experience is expressed by
coming to quick solutions to familiarish problems and considered solutions to
unfamiliar problems. And with experience comes intuition about what is and
isn't so important. There is just no way to move braing-teasers to the
important side of an experienced intuition when the problem domain resembles
that in which a mature individual is experienced.

When I was actively providing advice on the Architectural Registration
Examination, I used to see this all the time with the Site Design test. The
test gave the test candidate ninety minutes to organize several components on
an unfamiliar site against a set of competing requirements and constraints. A
common rant in the discussion forum was "I failed even though I've been laying
out sites professionally for {N} years," where {N} might be from three to ten.

The first ninety minutes of real world site design consists of opening the
civil engineer's email, creating a directory to for the project, saving the
attached CAD file, cleaning it up enough to be usable for architectural design
purposes, printing the regulatory requirements for the project file, talking
with the principal-in-charge about the client requirements, and then going to
lunch because it's been four hours and maybe starting on the design in the
afternoon or later in the week because that's the way the world works and the
client requirements will probably change anyway.

Which is how experience made it easy to fail the test because of the ways the
test did not reflect the real world. The real world has depth and a lot it-
depends and experience pays off precisely because it handles the depths and
makes informed choices about all the it-depends.

Or to put it another way, _Fizz-Buzz in TensorFlow_ ,
[https://joelgrus.com/2016/05/23/fizz-buzz-in-
tensorflow/](https://joelgrus.com/2016/05/23/fizz-buzz-in-tensorflow/)

------
omosubi
I can't believe no one has mentioned writing - try thinking about something
you strongly believe in (but others disagree with, like a
political/philosophical view), then write out your argument for why it is
true. Then write out what you think your opponent believes and think about how
they would pick apart your argument. Then rewrite your side again. Have
someone else read both sides and critique each.

Also try explaining how to do some task. Give it to someone else and, based
only on your instructions, have them try and do the thing you laid out. We're
they able to do it effectively? What questions did they have and where did
they get confused? These will help you improve your explanation and argument
skills.

------
westurner
Problem solving:
[https://en.wikipedia.org/wiki/Problem_solving](https://en.wikipedia.org/wiki/Problem_solving)

Critical thinking:
[https://en.wikipedia.org/wiki/Critical_thinking](https://en.wikipedia.org/wiki/Critical_thinking)

Computational Thinking:
[https://en.wikipedia.org/wiki/Computational_thinking](https://en.wikipedia.org/wiki/Computational_thinking)

> _1\. Problem formulation (abstraction);_

> _2\. Solution expression (automation);_

> _3\. Solution execution and evaluation (analyses)._

Interviewers may be more interested in demonstrating problem solving methods
and f thinking aloud than an actual solution in an anxiety-producing scenario.

[https://en.wikipedia.org/wiki/Brilliant_(website)](https://en.wikipedia.org/wiki/Brilliant_\(website\))
;

> _Brilliant offers guided problem-solving based courses in math, science, and
> engineering, based on National Science Foundation research supporting active
> learning.[14]_

Coding Interview University: [https://github.com/jwasham/coding-interview-
university](https://github.com/jwasham/coding-interview-university)

Programmer Competency Matrix: [https://github.com/hltbra/programmer-
competency-checklist](https://github.com/hltbra/programmer-competency-
checklist)

Inference > See also:
[https://en.wikipedia.org/wiki/Inference](https://en.wikipedia.org/wiki/Inference)

\- Deductive reasoning:
[https://en.wikipedia.org/wiki/Deductive_reasoning](https://en.wikipedia.org/wiki/Deductive_reasoning)

\- Inductive reasoning:
[https://en.wikipedia.org/wiki/Inductive_reasoning](https://en.wikipedia.org/wiki/Inductive_reasoning)

> _This is the [open] textbook for the Foundations of Data Science class at UC
> Berkeley_ : "Computational and Inferential Thinking: The Foundations of Data
> Science" [http://inferentialthinking.com/](http://inferentialthinking.com/)

------
dave_sid
Brain teasers are really useful for job interviews where the role involves
solving brain teasers. Other than that they can get in the sea.

~~~
qbantek
This.

I am about that age (that I guess the OP is) where, luckily for me, I have
created a curriculum and experience that will be wasted solving brain teasers.

Haven't interviewed in a good while (at least not from the interviewed side),
but if the interview consists of 'how much orange juice is consumed in the US
per day' kind of questions, I'd probably excuse myself, thank everyone for
their time and look for greener pastures elsewhere.

------
daniel-cussen
Fish oil is a good one. It's supposed to prevent Alzheimer's if you take one
gram a day, and it may improve your eyesight and heart at that dose.

You can take five a day. You can take 10. People with heavy brain damage (many
minutes without oxygen) take 15 a day for six months to learn to walk and talk
again, and they get recover.

------
dilippkumar
Joe Rogan recently had Dr Andrew Huberman on his show [0]. Dr Huberman had a
lot of fantastic information about changes in mental plasticity and how to
triggering learning in adults.

[0]
[https://m.youtube.com/watch?v=gLJowTOkZVo](https://m.youtube.com/watch?v=gLJowTOkZVo)

~~~
doesnotexist
Joe Rogan spam is an invasive species.

~~~
loquor
Friend, I just finished listening to the podcast after seeing this comment. It
is genuinely relevant. The episode is full of useful information related to
brain plasticity that OP would benefit from. Don't dismiss all of a creator's
content as spam.

------
guerrilla
I think both math and (analytic) philosophy can help. When I say math, there's
two different things I have in mind. One is just solving problems. Get any old
text book at your level and start doing homework problems. Same works for
physics. The other thing I have in mind is theorem proving. Look at Paul
Halmos' book on Naive Set Theory for example or pick something more at your
level.

As for philosophy, trying to pin down subtle distinctions and following the
extremely abstract arguments could help. You could start there with text
books, or reading in the history of philosophy like Aristotle, Plato,
Descartes or maybe by looking up concepts and problems you're already familiar
with in SEP.

Good luck and have fun.

[1] hhtp://plato.stanford.edu/

------
etrabroline
If you just care about brain teasers, caffeine is quite effective at inducing
small temporary increases in cognitive ability and is totally safe. Try having
a big 'ol cup of joe before interviews.

If you want to learn how to think more critically, you need to force yourself
to continuously engage new ideas and learn to recognize an author's
motivations and biases while still evaluating their arguments objectively,
putting aside your own past conclusions temporarily in order to understand
their argument. Then do the same for ideas you have previously agreed with,
and see which ideas hold up to scrutiny. Only then can you truly call
conclusions your own.

~~~
giantg2
Listening to Beethoven before a test is also known to induce a small cognitive
gain for 15 minutes after listening.

------
fistfucker3000
Meditation can help maintain neuroplasticity and help you in many other parts
of your life as well. I recommend the waking up app for a good intro

[https://www.wakingup.com/](https://www.wakingup.com/)

------
EForEndeavour
If you haven't already, check out
[https://projecteuler.net/](https://projecteuler.net/). It's a huge collection
of logic problems of varying difficulty that require a mix of math and
programming to solve. There are 723 problems at the time of this writing, and
a new one is added each week. After solving a problem (you need an account to
submit solutions, but can view all problems anonymously), you get access to a
discussion thread where you can gawk at the often mind-blowing solutions that
other solvers have hacked up in all kinds of languages.

------
runjake
I notice the same issues as I approach 50.

Here's what seems to work for me:

1\. Plenty of cardiovascular exercise.

2\. Eat well, including plenty of green plants.

3\. Get plenty of sleep.

4\. Limit online consumption and other unimportant inputs (TV, gaming,
podcasts, etc).

5\. Practice being bored^W^Wmindfulness. This could be meditating, or just
sitting outside contemplatively, or not consuming content while performing #1.

6\. Keep spot checking yourself for where you're coming up short with the
above 5 items. It's all too easy to fix the issue, feel great, and then fall
out of the above habits. But you can't. You've got to stick to the plan.

------
bingobongo1
Develop Shamatha, which is a calm abiding mind, meditative equipoise, single
pointed concentration.

Then engage in analytical meditation, typically known as Vipassanā in the
Buddhist tradition, but essentially it involves analytically decomposing
whatever you're meditating on.

I realized that before I ever dove into Tibetan philosophy that I was
developing these two as I designed and constructed software (as I'm sure a lot
of us do).

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treya
1) Think hard about things that you have to work at in order to understand 2)
Engage in exercise that regularly includes anaerobic intensity 3) Sleep well
and deeply

Learning is brain growth that occurs as a result of thinking, largely during
rest and sleep following the activity. Exercise will increase the amount of
growth that occurs (mentally and physically), and good cardiovascular health
is effectively the same thing as good brain health

And, maybe obviously, practice the brain teasers and interview questions. They
are a skill that is not the same thing as being mentally sharp

------
aj7
I hope you can afford my answer. It’s time to live your life for you, not
“them.”

~~~
treyfitty
I agree, don’t get me wrong. I’m all for that mentality and generally draw the
boundaries between work and life. However, in this precarious time, I need to
find another job.

------
giantg2
One thing I haven't seen mentioned is that you could use Lions Mane mushroom,
or it's extract. There was a double blind study from Japan that shows this is
a nootropics.

Also, brain teasers are a BS way to interview. One of the best interviews I
had was a mock architecture session (I didn't get the job). They gave me an
overview of a project, told me to use AWS tech, and let me ask questions as I
worked through a rough architecture.

------
austincheney
Always be skeptical, objective, and learn to deeply appreciate originality.

I wrote this yesterday after confronting somebody saying something short-
sighted:
[https://github.com/prettydiff/wisdom/blob/master/faulty_prem...](https://github.com/prettydiff/wisdom/blob/master/faulty_premise.md)

~~~
thereticent
Not a bad read. In the opening paragraph you conflate argument validity with
argument soundness, though. Thanks for the link.

------
bassrattle
Grey matter is where knowledge is stored. White matter is where the
connections are. Enhance those connections. For that, I recommend learning to
juggle.
[https://www.sciencedaily.com/releases/2009/10/091016114055.h...](https://www.sciencedaily.com/releases/2009/10/091016114055.htm)

~~~
EForEndeavour
This is a gross overextension of the results of that study. From the article
you linked, emphasis mine:

> ‘This exciting new result raises a lot of questions,’ says Dr Johansen-Berg,
> ‘MRI is an indirect way to measure brain structure and so _we cannot be sure
> exactly what is changing when these people learn._ Future work should test
> whether these results reflect changes in the shape or number of nerve
> fibres, or growth of the insulating myelin sheath surrounding the fibres.’

> _‘Of course, this doesn’t mean that everyone should go out and start
> juggling to improve their brains._ We chose juggling purely as a complex new
> skill for people to learn.

If OP takes your advice, they'd end up being decent at juggling, but at the
huge opportunity cost of _not_ practicing _actual_ critical-thinking skills
directly, or reading articles and books relevant to their target domain of
expertise, or some other approach to prepare for interviews and a career in
data science that's more effective than juggling, of all things.

Besides, OP already said they've been juggling two kids!

------
sitkack
Exercise, sleep and shooting the shit with friends has the biggest impact on
my perception of mental acuity.

~~~
giantg2
Ah, yes. I forgot that social engagement is a factor in prolonging cognitive
function.

------
gruglife
Although not directly related to critical thinking, product questions or brain
teasers but what works for me is reading and reading whatever floats my boat.
I consider it weight lifting for the brain.

------
mindhash
It just takes practice. I had to do the same. I started solving Sudoku, George
summers puzzles.

In the process, I could develop a general process to solve problems.

Using systems thinking helped a lot.

