Why is intuition so fast?

Last week we discussed intuitive thinking or "trusting your gut," looking at situations in which it is advantageous and when it is not. This week, I'd like to continue the discussion by looking at why intuition is so much faster than its more methodical counterpart.

The answer is largely two-fold. On the one hand, intuition is heavily reliant on memory, which is itself a fast process. For example, if I asked you what the product of five and six is, your intuition would likely fetch from memory the number thirty: the correct answer. This is true for any problem for which the solution has been committed to memory and recalled many times. This offers some insight as to both why intuition is fast–successive recalls become progressively faster–as well as why it is useful–it saves you a lot of time in the long run.

Let's revisit the first example from last week:

The chief of a fire brigade walks into a burning house. They can't quite put their finger on it, but something seems off. A sense of dread washes over them as they begin to shout "clear the house!" The firefighters in the house quickly flee from the building, and just in time; the building collapses only minutes later. The fire chief feels relief knowing that their call prevented a catastrophe, but they still don't know why they made that call to begin with.

A fire chief likely has been on the job a substantial amount of time, and as such has likely seen a vast array of burning buildings. When the fire chief entered the burning house above, they intuitively took account of their surroundings before intuitively concluding that the house resembled others buildings which had collapsed in the past. With only this intuition of similarity and limited time, the fire chief trusted their gut.

Memory is a very important part of intuition, but it's not the only one. It would not have been enough for the fire chief to have simply recalled memories of burning buildings; the information needed to be processed in some way. In the fire chief's case, the comparison was one of similarity. Take a look at the following two questions:

1. Is this house going to collapse?
2. How similar is this house to houses I've seen collapse in the past?

The first question is certainly the question to which the fire chief wanted to know the answer, but there are some key problems with answering it. There are a multitude of factors which influence whether the house will collapse (e.g. "what year was the house constructed," or "which walls in this house are load-bearing", or "what percentage of this structural beam has been combusted"), many of which are impossible to know the answer to either in the moment or in general. This is called objective ignorance, and it makes the first question impossible to answer with certainty. The second question, however, relies on information which is readily available as well as comparisons which can be made with little mental effort. The result is a mental substitution where a more difficult question is replaced with an easier one.

The process by which an easier question is substituted for a harder one is a mental shortcut, otherwise known as a heuristic. If you've heard the word "heuristic" used before, it likely arouses some negative feelings. I think it's safe to say that heuristics have a bad wrap, often cited as a sort of gotcha in online discussions. Indeed, the study of heuristics has overwhelmingly focused on the various cases in which heuristics lead to errors, but I think this has itself led to an overly harsh view of heuristics. Later on, I intend to explore the many heuristics people employ to make decisions.

Up next: Biased against bias? Why we dislike bias, and why we sometimes need it.