The Hare and the Tortoise: two systems in our brain

Are you truly rational? Someone could say "well, not always in my personal life, but at work I'm a very rational person". Or you might believe that you're acting rationally "most of the time." But decades of cognitive science tell us that's almost certainly an illusion. We are hardwired to take mental shortcuts and rely on automatic modes of thinking that lead us to biased views and systematic errors when making all kinds of decisions.

A half-truth is more dangerous than a lie. (Thomas Aquinas)

Some problems are just too hard to solve in a detailed and exact form. Sometimes, they are impossible; in most cases, just not worth it. Heuristics are strategies to simplify such problems and arrive at approximate results that aren't optimal or perfect, but generally pretty good, by a fraction of the effort.

Perceiving the world around us is one of those complex problems. At any moment, our brain bombarded with roughy1.4 MB per second of data from the five senses. If you're daily awake for 16 hours, that's 80.6 GB of sensory inputs every single day! Dealing with all this data by "brute force" would be impossible, and even trying would be a waste of precious resources. So our species evolved several strategies to make quick and intuitive decisions based on limited or simplified inputs. More than that, our brain deliberately ignores most of the information around us, in order to focus on performing a few crucial tasks with high efficiency.

Beyond the simplification of sensory data, similar strategies were developed to deal with more abstract problems, such as classification, likelihood estimation, and even the shaping of our beliefs.

But the world changed a lot since we developed our big homo sapiens brain, equipped with its cognitive patterns. After millions of years of having to worry about, basically, escaping predators, finding food, and reproducing, today's society throws at us increasingly complex problems on a daily basis. The good news is that we do have a very specialized brain circuitry that is specialized in tackling exactly those kinds of problems... the bad news: it's a very lazy system!

A lot of our current understanding about such cognitive processes comes from Daniel Kahneman, the psychologist who won the Nobel prize in Economics (that alone, worth mentioning!) for his work with the late Amos Tversky on decision making, more specifically on Prospect Theory. Since I read Kahneman's "Thinking, Fast and Slow", an amusing compendium of decades worth of research on cognitive theory, I'm fascinated by this topic.

Kahneman introduced the two main modes of operation adopted by our minds by the (not very descriptive) names of Systems 1 and 2:

• System 1: operates quickly and automatically, with little effort and very limited conscious control
• System 2: accessed by deliberate effort for dealing with more complex and demanding mental activities, requiring more energy and attention

Some general characteristics of the two systems can be seen in the diagram below:

But it's not like our brain is split in two, with areas dedicated for each of those modes of operation. Rather, the two systems co-exist in the whole brain, sharing resources and functions. This split is conceptual, not literal.

Another point that separates the two systems is how frequently we are engaging each of them. While System 1 cannot be "turned off", System 2 is just being used for about 5% of the time:

Since System 1 is responsible for most of our daily reasoning, and we rarely notice how it does it, let's go through some important features of our "fast" way of thinking:

• Generates impressions and inclinations, or just jump to conclusions; when those are validated by System 2, they are solidified as beliefs
• Prefers information that is easy to process, linking cognitive ease to truthfulness and pleasure (a very useful presentation tip, by the way!)
• Represents sets and populations by stereotypes, frequently overgeneralizing and ignoring basic probability rules for inference
• Always tries to replace a difficult, complex issue with an easy and straightforward one, a.k.a. heuristics (as well-put by H. L. Mencken, "For every complex problem there is an answer that is clear, simple, and wrong")
• More sensitive to losses than to gains (loss aversion), commonly choosing decisions that contradict what the economic theory predicts for a rational agent, i.e. the maximization of potential returns
• Ignores ambiguity and tends to reduce the potential for doubt, leading to a kind of "artificial certainty"
• Plus a ton of other biases...

Although these shortcomings have been present for a long time, in a society increasingly polarized around beliefs and with little room for truly rational thought, it's more important than ever to start recognizing these cognitive biases and find ways to mitigate them.

But System 1 is not all traps and disappointments. When properly guided by training and deliberate decisions (let's wake that lazy System 2 for that!), it can be a powerful tool:

• After proper training, System 1 generates quick and accurate "guesses", and reliable intuitions (this is the central topic of Malcolm Gladwell's excellent book Blink: The Power of Thinking Without Thinking)
• It can be programmed to detect certain patterns and mobilize attention or take some predefined action

As managers and knowledge workers, decision-making is at the core of our daily activities. The quality of our decisions can be the difference between tremendous success and catastrophic failure. Therefore, it's really important to better understand how these cognitive biases affect our thinking and how to overcome them. In the next article, we'll dive into some key groups of cognitive biases, how they manifest at work, and explore some tools to keep them in check.

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