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System 1 or System 2 thinking – which are we all using?

Posted by Jonathan Klane on Apr 13, 2021 11:39:53 AM

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Did you ever drive someplace, only to arrive at your destination and think, "I don't even remember driving! How the heck did I get here – and in one piece?!" Or perhaps when you were surprised by an animal or child darting out into the road, and you braked or swerved just in time to avoid hitting it? And you thought, "Thank goodness – that was close!"
If you're like me and most of us, you have, and it's a normal part of how our magnificent brain can work – sometimes. We can and often do make split-second decisions without consciously thinking about them. It was a survival skill and up-selected evolutionary trait that we thankfully continue to have and use today.

It's called fast thinking or system 1. And as I'm sure you could guess, the corollary or companion to it is indeed slow thinking or system 2. In the 1970s, Daniel Kahneman and Amos Tversky did a ton of studies on human behavior and decision making, and they learned a lot. Like why we care more about a loss than we do about an equivalent gain? Or why the first number have such an anchoring effect? And why do we throw good money after bad? Basically, they studied our many cognitive biases – how we make decisions that don't appear rational at first glance. And did I mention that Daniel Kahneman got a Nobel Prize in Economics Sciences for it? And he wasn't even an economist – he was a behavioral psychologist and researcher. But their groundbreaking 1974 article, Judgment Under Uncertainty: Heuristics and Biases, changed how we see risk, perceptions, and human decision-making.

I'll be discussing these and many other of our cognitive biases in future micro-blogs in this series – "Risk is a 4-letter word". But what about all of this fast vs. slow thinking? Let's come back to that. It turns out that we don't do a lot of heavy cognition if we can avoid it. Our brains find workarounds to reduce the energy load.

Imagine that you're driving, and you see something that looks like a child; you'll likely swerve to avoid it – a good thing, of course. What if it was just a plastic bag caught by a breeze or an animal? Our brain reacts to what it thinks it might be as opposed to what it is.

If you want a literary allusion to fast thinking, look no further than Spiderman. Do you recall his Spidey sense tingling? And his super-fast reactions? Yes? Well, those are great examples of this non-analytical intuitive, fast thinking. Now, you don't have to be a superhero to have and use quick thinking (though I'm sure it'd be nice to have Spidey sense in a pinch!). Here are a few examples you may have experienced yourself.

You're sitting at the dining room table enjoying dinner with the family. One of your sweet children reaches for a dish and knocks the vase with the fresh-cut flowers tipping it over. And as if in slow motion, your arm shoots out, and you barely manage to catch the vase before it crashes. Your loved one says, "Wow, what a catch! How'd you do it?" And you say, "I don't know, I just reacted." Fast thinking saves the day. Sometimes.

You're driving and watching the road when all of a sudden there's a dog in the street! You swerve to the right, barely avoiding hitting the poor thing, likely killing it had you not cranked the wheel. But now you're skidding through into the breakdown lane and onto the shoulder going down the rolling slope! You're braking and trying to hold the wheels straight! You finally come to a stop. You're sweating and thankful that it wasn't worse. And you hope that dog is okay.

You're on your way to getting your usual coffee, and while walking, you're looking at your phone, and you get to the door without a mishap—that time.

You get your coffee, and you're looking at your phone as you walk off the curb and "Beeeep!" as a car goes whizzing by. You jump back, heart-pounding as the driver curses you out. And you think, "Boy, that was close! I've got to pay better attention!"

You're in a lab decanting some sulfuric acid, and you're startled by a loud noise. You react and swivel, and in your fast thinking turn, the acid splashes out, spattering your arm! You turn one way, turn back, and you run to the sink! You drop the glassware in the sink, turn on the cold water, and stick your arm under the flowing water. A labmate rushes over and says, "Let's get your lab coat off to wash your arm better!" You do so, but you can't wash your whole arm, and you now say, "Oh my God, I think it got on my face!" The lab mate has to help get you into the emergency shower—much more fast thinking, which unfortunately didn't help you.

These and similar situations happen to us all. Sometimes we notice, mostly we don't pay attention. Sometimes fast-thinking saves our butts, and sadly, too often, it doesn't. Try going without it. You can't. Try insisting that someone "Pay better attention" or "Needs to be more careful." Really? Try it consistently. I'll bet you can't sustain it. Don't expect others to either. Or as Daniel Kahneman put it,

"It is wrong to blame anyone for failing to forecast accurately in an unpredictable world. However, it seems fair to blame professionals for believing they can succeed in an impossible task."

Which system of thinking are you using when it comes to risk? And which system are those around you?

Coming Soon: Why is "threat to value" key to understanding decisions?


Kahneman, Daniel. (2011). Thinking, Fast and Slow. Farrar, Straus and Giroux.

Kahneman, Daniel and Tversky, Amos. (1974). Judgment Under Uncertainty: Heuristics and Biases. Science, 185(4157):1124-31. DOI: 10.1126/science.185.4157.1124.

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