Take a look at the following image, what do you see under the arrow?
Now take a look at this other image, what do you see next to the arrow?:
If you are like most people, you answered ‘B’ in the first image and ‘13’ in the second one. But did you notice that it’s the same symbol in both cases?
So, what’s going on? Is it a B or a 13? The thing is that we use both the stimulus and our ideas to assign meaning to it, that is, to perceive it either as a letter or as a number. In this particular case, the context gives us the clues to figure out how to interpret the ambiguous symbol.
The interaction between the sensory and mental realms is permanent, both are necessary to build a model of the world that enables us to interact with it, deal with it, make decisions in it.
However, in many situations the physical world isn’t sharp enough to create a precise mental model. In those cases our ideas become more important because they are used to fill in the blanks (as in the above experiment). And sometimes our ideas are SO strong, that bias our perceptions towards what we believe to be true. For instance, take a look at these two series of coins tossed:
We have a preconception of ‘randomness’ that equals ‘variable’ and that idea makes us believe that one series is more probable than the other. We expect a mixture of tails and heads. Therefore, if we only get one kind, the series doesn’t fit in the category ‘random’. Yet, the result of any toss is 50%, heads 50% tails, it doesn’t matter what came before. Of course if we were to toss the coin an infinite number of times, we would get heads half the times. But in a small number of tosses, this may not happen. This misconception of chance is pretty common: the (wrong) notion that chance corrects events to keep a neat balance.
Other times we use available data to create categories, leaving out relevant but unavailable information. For instance, an entrepreneur that is considering launching a new business will do market research, will find out some products that succeeded and some that did not. But she won’t be able to take into account the many attempts that failed because those are invisible. The data at hand won’t be representative of reality, and therefore, the mental model created will be flawed. This bias has its own name, the survivorship bias. It’s one of the reasons people keep buying lottery tickets: every sunday there’s a winner that is in the spotlight, and tens of thousands of losers don’t get any exposure. Can you imagine what would happen if every sunday all the non winners were in the news? Or if the winner said: I have played every sunday for the past 20 years, it was about time I won!
So, next time you have to interpret an event, ask yourself: what ideas are tainting your perceptions?