Humans: not optimised for logic

Below is a puzzle that will soon be 50 years old. It was developed in 1966 by Peter Wason, a cognitive psychologist interested in the often illogical nature of human reasoning. The puzzle is a very simple logic puzzle and involves no tricks. Yet, across multiple studies less than 10% of people give the correct answer. See how you do:

Logic puzzle 1

There are four cards with a number on one side and a colour on the other. If the number is even, the card must be red on the other side.

Which cards need to be turned over to check if the above rule is followed?

4 9 red green

Which cards could violate the rule?

Keen for the answer? Well… just wait a moment. Let’s try another puzzle:

Logic puzzle 2

You work at a licensed restaurant. Your boss asks you to make sure all patrons who are served alcoholic drinks are over 18.

Which patrons do you need to check?

Patron 1

Patron 2

Patron 3

Patron 4

Drink: tea

Drink: wine

Drink: ?

Drink: ?

Age: ?

Age: ?

Age: 47

Age: 15

Okay. Now let’s check how you did.

  • The correct answer to logic puzzle 1 is the first card (number 4) and the last card (green).
  • The correct answer to logic puzzle 2 is patron 2 and patron 4

Chances are, if you are like most of us, you had the answer to puzzle 1 wrong but were correct for puzzle 2. If you got both right then, congratulations! You are an unusually logical thinker.

But here’s the really interesting thing: From a logic point of view, these are both the exact same puzzle. Both puzzles involve testing a rule of the form “If P then Q”. The most common answer to puzzle one is to select the cards named in the rule — the 4 and the red. This would be logically equivalent to a bottleshop owner asking for ID from anyone buying alcohol who looks older than 18.

Often there is some degree of misinterpretation of the rule as if it read “all even cards, and only even cards, will be red on the other side”. However, the answer most commonly provided is incorrect even for that interpretation: for that rule you would need to turn over every card to confirm the rule.

Somehow the nature of the content of the second puzzle makes the correct answer “pop out”, while the first puzzle exposes limitations of our human reasoning. There are several theories about why we are so much better at the second variation of the same puzzle.

One theory is that our brains are optimised to detect violations of social rules — in this case the rules prohibiting underage drinking. Being good at detecting and enforcing social rule violations may have significant survival value — whereas being able to detect violations of arbitrary logical rules may have very few implications for survival. Another theory is that the effect is a feature of how we process information by relevance while minimising cognitive effort.

Whatever the explanation, here is what I would see as the important take-home lesson: Humans aren’t logical. We can be absolutely convinced we are right while being at the same time obviously wrong. We jump to conclusions. We ignore information that contradicts what we already think. We are messy creatures, and we can’t change that. However, by understanding our nature, and limitations, we can be a little less vulnerable to some of their consequences — perhaps a little less hurt by assuming, when our friend says “You’re five minutes late”, that it means “I’m angry with you”, for example.

Hungry hungry hippocampus: Diets and your brain

DSC_6903Wanting to eat better, lose weight or improve fitness is one thing … for many of us, actually achieving these goals can prove elusive. Common sense is not always enough to achieve lasting change, and there is such diverse and too often contradictory information out there on health, fitness and dieting.

ABC’s All in the Mind aired a story in late October exploring some lines of research that may shed some light on some of the challenges of dieting – and how we might overcome them.

You can listen to the full program, or read the transcript here: Diet on the Brain

Particularly interesting in this program is reference to some research on how the brain might be “trained” to prefer certain types of food, depending what you typically eat when you are most hungry. More information on that research can be found here:

Train Your Brain to Prefer Healthy Foods

Neuroplasticity in action

It’s likely that by now you have at least heard the term “neuroplasticity”. Our understanding of the human brain’s capacity to rewire itself has grown dramatically over the past few decades. We have written about it previously in our blog post Rewire your brain: neuroplasticity FTW!.

It’s one thing to hear about neuroplasticity. But it is something else altogether to see it in action. Today I stumbled across this youtube video:

There are lots of skills that are complex and difficult to master, for which the development of new neurological wiring through continual practice will be essential to mastery. But rarely do we see such a <em>dramatic</em> challenge to achieving the most rudimentary level of competence. Why is this bike so difficult to ride?  If we reversed the steering in a car people would very quickly be able to adjust. Anyone who has played a reasonable number of flight-simulating computer games will know how quickly that adjustment can occur, because a proportion of those games reverse the vertical control axis. Adjusting to that can be accomplished in hours. It took <em>eight months</em> for the presenter of this video to be able to ride this bike.

The challenge with reversed steering on a bike is that steering is not <em>only</em> used to control your direction, but constant small adjustments are made to maintain balance on the bike. With the steering reversed there is almost <em>no room for error</em> that would allow the brain to try an option, realise it is producing the wrong result and adjust accordingly. It is worse than learning to ride the <em>first</em> time because the brain is predisposed by existing wiring to select a set of motor responses that are the precise <em>opposite</em> of what are needed, amplifying any imbalance instead of correcting it.

…so the thing that amazes me most, watching this video, is that even under circumstances that are tremendously prejudiced to failure, the neuroplasticity of the brain makes success possible. What might your brain be capable of that may seem impossible to you today?

Bicycle leaning against a wall

“Bicycle” by fedeanimationCC BY 2.0

The Science on Mindfulness

Mindfulness forms an important part of a range of strategies we use at Thrive Wellness to facilitate psychological well-being. So far we have never written on the subject on our blog. Now, once again, the Radio National program All in the Mind has done a great job summarising what mindfulness is and the current state of the science on its usefulness. Also included are some good personal accounts of its benefits.

Have a listen to the program, or read the transcript, here: All in the Mind – On being mindful.

Cape Naturaliste Lighthouse - WA

The ABC Monitoring worksheet

The ABC Monitoring worksheet is for identifying beliefs that play a role in producing our emotional and behavioural reactions to situations. Triggering situations are recorded in the “A” column, and reactions in the “C” column. Thoughts and beliefs that produced those reactions are then recorded in the “B” column. It is useful to use this tool in conjunction with a list of common cognitive distortions so that unhelpful beliefs can be categorised according to relevant cognitive distortions.

Describe Your Emotions worksheet

Sometimes our ability to process emotions while still engaging in logical processing of information may not be as developed as we would like. This can contribute to problems such as saying or doing things when we are angry, frightened or sad that we might later wish we had said or done differently. The Describe Your Emotions worksheet, adapted from a tool in the Dialectical Behavior Therapy Skills Workbook by McKay, Brantley, Wood & Marra, is a tool you can use to train yourself over time to build stronger communication pathways between emotional processing centres and other information processing centres in your brain.

Radio National program on Borderline Personality Disorder

The All in the Mind program on ABC’s Radio National recently aired a good segment on effective treatments for Borderline Personality Disorder (BPD). Treatment is out there, and it works. To listen to the program, or read the transcript, follow the link here: Borderline personality disorder—what works?

On the program Catherine Bennett, formerly diagnosed with BPD, says the following:

BPD is not a choice, but recovery is. And like any mental illness, no one ever chooses to have a mental illness, but fighting for recovery, having a life worth living, that’s a choice. And making that choice is the first step.

If you would like to know more about BPD, you may also like to read Life on the Line – what is Borderline Personality Disorder?