Ask HN: How to start developing critical thinking?

Critical Thinking is not something you turn on and off. It is a way of life.

Like any other attainable skill, it becomes better with practice.

First, start reading descent novels- any kind of novel that you will. It can be Stephen King-type, Tolkien-type, Dune-type- anything.

Start your critical thinking practice with humans. Empathize with them. Also become a little cynical. Try to find out someone's motives, background, etc. behind what they do and tell.

This is way you can practice critical thinking a lot. Never judge anyone. Judgmental mentality clouds clear thinking.

Try to understand where the character of a novel comes from, why they do what they do. What would you have done? These lead to better situation-reading for any situation.

Then, do anything that requires critical thinking. Play chess. Learn HS/college level math. Solve a lot of problems yourselves.

Look at past questions from coding competitions. Do not worry about the time. Solve them.

To be good at critical thinking, just practice thinking.

I also suggest maintaining a journal/blog. Here you write your heart out, simply walk the steps that you have traveled while solving a problem. If there is a thought clouding, just write is down clearly. Do not worry about writing quality. Just write.

Writing makes thinking mamy times better. And I do not say that lightly.

Maintain habits where you practice critical thinking.

A good place to start is by reading the books and memos of Howard Marks.

His analysis of the stock market and investing is a prime example of critical thinking.

I would start by taking the answers given here with a hefty portion of salt.

It is fairly shameful to answer this question with authority, so largely you are selecting for shamelessness among the answerers. I am revealing my own shamelessness then, now, by answering you.

To start with, the main thing that is required for my process is an emotional investment. This isn't dispassionate analysis. Truly critical thought requires, in my experience, a strong fear of being wrong. I do not believe there is a shortcut to this. Fear is a powerful motivator, and if you are not afraid of being wrong, then why do you care at all?

The fear drives an internal adversary that tries to find flaws in all encountered beliefs. Preempting the arguments that could be used against you if you were to hold them. So afraid are you then of being wrong, that you will change your mind. You will do this even if it means you will disagree with people you don't want to disagree with. You will fear being wrong more than not agreeing with them.

This fear should be relentless, but it does not have to be unpleasant, and by submitting to it completely, you can gain true confidence in your beliefs. The adversarial process does not always converge upon the truth, but it does at least converge on something that is hard to refute.

I have one more piece of advice, but I'm not sure how applicable it is to everyone. There is no such thing as true or false for beliefs. Or rather, you should not act as if there is. Whether a belief is true or false is one of the less usefull things about it. Instead, you should consider beliefs as resting on top of each other, in a sort of jenga tower. Since you have committed to potentially changing your mind about anything, it is far more important to keep track of why you believe things, than that you believe them. If you then do change your mind, you can be less wrong in a lot of other ways for free just by letting the jenga tower above it fall down.

There are a lot of approaches, and some I agree with are mentioned in the comments. One additional thing that's important is trying to always assess the quality of the information you come across, as a first step.

Even the smartest person can make bad judgements if they're relying on inaccurate information. Thus, anything like critical thinking about a topic has to start with some kind of test. One thing to look for (and this is a very math-centric way of looking at it) is to look for inconsistencies, i.e. if two pieces of information are claimed to be reliable but they appear mutually exclusive, then there is probably a problem with either one or both pieces.

There's a web page listing many similar useful logical tests for the quality of information (and arguments) that's been around for a long time. Going through the list is a good exercise.

http://www.nizkor.com/features/fallacies/

Example: Description of Biased Sample

This fallacy is committed when a person draws a conclusion about a population based on a sample that is biased or prejudiced in some manner. It has the following form:

    Sample S, which is biased, is taken from population P.
    Conclusion C is drawn about Population P based on S. 

The person committing the fallacy is misusing the following type of reasoning, which is known variously as Inductive Generalization, Generalization, and Statistical Generalization:

    X% of all observed A's are B's.
    Therefore X% of all A's are Bs. 

The fallacy is committed when the sample of A's is likely to be biased in some manner. A sample is biased or loaded when the method used to take the sample is likely to result in a sample that does not adequately represent the population from which it is drawn.

Here's a practical critical thinking heuristic. When you want to practice your critical thinking, try these five words:

- READY? Center yourself (that means notice and acknowledge your emotional state which might be pushing you toward one conclusion; then counter that); Consider whether you are qualified and prepared to think critically on the subject at hand.

- HUH? Say "huh?" to yourself as a reminder that you might not understand the matter at hand. You might be miscomprehending the words entirely. Check that understandinf.

- REALLY? As to any matter of alleged fact, ask how we know it is true?

- AND? Whatever is being alleged, start wondering what ELSE is true that you have NOT been told? Sometimes errors of thinking are related to errors of scope and perspective.

- SO? Ask how the matter at hand is important. What difference does it make? Who cares?

These five words are a sort of mental swiss army knife for me when I have to critique my own thinking or someone else's.