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Critical Thinking

By September 10, 2021November 2nd, 2021Approach, wisdom

The quality of your life is determined by the quality of your decisions.

And the quality of your decisions is determined by the quality of your thinking.

We’re not talking about intelligence, by the way. We’re talking about thinking, and making good decisions.

Here’s a thinking test that supposedly only 50% of students at Harvard got right.

It’s a test developed by Nobel prize-winning psychologist .

Are you ready to test your thinking? Here’s the question:

A bat and ball together cost $1.10. The bat costs one dollar more than the ball. How much does the ball cost?

If you know right away go ahead and answer.

If you want to deliberate, feel free.

When you get to the bottom of this email you’ll see the answer.

The question appears in Daniel Kahneman’s book , which is about how our cognitive abilities get tripped up in common situations.

I’ve written before how we tend to make mistakes when we react too quickly. And this is especially true of reacting too quickly in our thinking.

If you want to improve your thinking and decision making there are probably several things you can do.

But, understanding common cognitive glitches (which plague all of us humans equally) is a great place to start.

So, reading Kahneman’s is highly recommended. And same goes for his .

Remember: the quality of your life is heavily influenced by the quality of your thinking and your decision-making.

The Answer

The answer to the question is: the ball costs 5 cents, the bat costs $1.05, and together they cost $1.10.

of why most people tend to get the answer wrong.

P.S. If you appreciate these kinds of observations, you might want to read this as well.


  • john says:

    This seems more like a primary school algebra problem, no?

    x + (x+100) = 110
    2x + 100 = 110
    2x = 10
    x = 5
    Ball = 5; Bat = 5 + 100 = 105

    I’m not familiar with Kahneman’s Fast and Slow — there’s only so much pop psychology one can absorb in a given lifetime and then, like a saturated sponge, one has to slough off there est. This just seems a matter of people not following a process?