Inevitable Illusions - How Mistakes of Reason Rule Our Minds

InevitableIllusions We're all familiar with optical illusions - where we think we see something that is in fact an illusion. The problem is that we create the three-dimensional world in our head based on the input of our senses and the rules that do that translation, and normally serve us so well, can be tricked.

It turns out that the rules used by other parts of our brain can be similarly tricked - giving rise to the term cognitive illusions.  Illusions that are independent of sex, race or IQ.  Massimo Piatelli-Palmarini is a cognitive scientist (actually a principle research associate for the centre for cognitive science at MIT and the director of the dept of Cognitive Science at the Institute of San Raffaele in Milan, so I guess he knows what he's talking about!) and his book Inevitable Illusions - How mistakes of reason rule our minds is intended as a layman's guide to these cognitive illusions.

Massimo describes the process as mental tunnels - the grooves that our brain just can't help getting themselves into.  For example the way we process probabilities, even simple ones, is open to all sorts of mental tunnels.  The simplest probably tunnel described is illustrated thus:

"I have just tossed a coin 7 times, and I ask you, who have not seen the result, to guess which of the three sequences below represents the sequence of results:


Go on, which one would you choose?  Having repeated this experiment many times we're assured that bets are placed in the order: 2, 1, 3.  The preference for 2 is very strong... and is an example of the most common cognitive illusion - mistaking typical for the most probable.  In fact, probability theory tells us that in seven tosses of a con, the probabilities are totally even and so ANY of the three are the right choice.

The result is that we find ourselves committing what Massimo describes, somewhat playfully as the seven deadly sins:

  1. Overconfidence - in our illusion lead thinking.
  2. Illusory correlations (magical thinking) - we reach results thinking they are based on logic when they're simply not.
  3. Predictability in hindsight - once we have the answer or facts we think we could have perfectly predict the outcome (this is a big one for historians).
  4. Anchoring - the first thing we notice incorrectly informs the conclusion of our thinking - the easy example here is: given 2 seconds tell me the result of multiplying the numbers 1 2 3 4 5 6 7 8 9 together?; your answer will typically be much lower than if you were asked: in 2 seconds multiply the numbers 9 8 7 6 5 4 3 2 1 together.
  5. Ease of representation- we are likely to report the things we can easily imagine or remember as being more frequent.
  6. Probability blindness - our intuitive ability to calculate probabilities is totally floored.
  7. Reconstruction under suitable scripts - a ridiculous end situation can look much more plausible if you take someone through a multi-step script of how 'a' could lead to 'b', which could lead to 'c', to 'd' and 'e' which would give you the end state. When the individual steps are unlikely, the overall result is so completely implausible as to be ridiculous - I loved his example of Othello - where Iago sets out to make Othello believe his beloved wife, Desdemona is unfaithful to him, by making up a plausible but deceptive scenario involving Desdemona's handkerchief; which ultimately leads to Othello killing her!  Massimo likes to call number 7 'the Othello effect'

Although I enjoyed the book, I sometimes found it a little awkward - Massimo took prolonged paragraphs to explain some simple concepts and on other occasions skipped over something that I didn't quite get.  So, overall I found it a little long winded but it certainly reveals some really interesting insights in to the way we think!

Format: Book, 209 pages
Author: Massimo Piattelli-Palmarini, Ph.D.