Heuristics

The human brain, despite its immense power and complexity, is not without limitations. This is evidenced by studies such as the Invisible Gorilla test. This is a simple test that asks to participants to watch a video of people passing a basketball between each other, and count the number of passes.

Within the video, a gorilla appears in the background. Participants that were counting the basketball passes rarely notice this, while ones who were just watching the video notice it straight away.

In other words, people’s response to the same set of circumstances and information can vary wildly, depending on what we are prioritising. Our brains use various mechanisms to prioritise certain pieces of information over others.

One such mechanism is the use of heuristics, or mental shortcuts, that our brains employ to speed up decision making. Heuristics are cognitive strategies or rules that simplify mental processes, allowing us to make decisions, judgments, and solve problems quickly and efficiently. Understanding these shortcuts can provide insights into decision-making behaviors.

The concept of heuristics was introduced by psychologists Amos Tversky and Daniel Kahneman in the 1970s, laying the foundation for much of our current understanding of heuristics. These concepts have since been widely adopted and further developed in behavioral economics.

Heuristics manifest in various forms, as in the use of trial and error, rules of thumb, or educated guesses. These strategies are not random. They are often based on past experiences, learned behaviors, or innate cognitive processes. For instance, an educated guess might be based on prior knowledge or intuition.

The primary aim of heuristics is not to achieve the ideal or optimal outcome. Instead, they serve to provide practical, quick-fix solutions that require minimal cognitive effort. This is known as the principle of 'satisficing', a term coined by economist and psychologist Herbert Simon. Satisficing suggests that people often make decisions that are 'good enough', rather than spending additional time and effort to find the best possible solution.

Heuristics are a double-edged sword: with enhanced efficiency, we compromise the quality of our decisions. But as Simon suggests, humans are happy with ‘good enough,’ especially when stakes are low. For instance, a reasonably healthy individual will not waffle over what to order for lunch. He’ll just order what he feels like having instead of running through all the possibilities and their possible consequences on his health and bank account.​​

Heuristics are also applied in practical contexts, such as the design of user interfaces. In websites and mobile applications, designers influence decision making by using a brighter color for the button they prefer users to choose while leaving the less preferred option with an unremarkable gray color. This leverages users’ tendency to notice and interact with objects that stand out visually.

Retail stores often contrast sale prices to their original retail price to influence purchasing decisions. This practice relies on the anchoring heuristic, in which people rely heavily on the first piece of information they encounter – the anchor – when making decisions. In this case, the original price serves as the anchor, making the sale price seem more attractive in comparison.

Heuristics also guide 'common-sense' decisions in everyday situations. When walking alone at night, we might instinctively avoid dark alleyways, likely because we associate such contexts with danger. In this case, we are drawing on the availability heuristic, or making decisions based on information that is salient to us. These are all examples of how heuristics can often serve as useful guides in our daily lives.

The concept of two-system thinking, as laid out by Daniel Kahneman in Thinking, Fast and Slow, provides a framework for laypeople in understanding the cognitive processes that underpin human decision making. Kahneman proposes that our cognitive functioning can be divided into two distinct systems, each with their own specialty.

According to Kahneman, system 1 thinking, which is fast and intuitive, might be employed when performing simple arithmetic or making a quick decision – 2 + 2 = 4, or crossing the street when the light turns green. Meanwhile, system 2 thinking, which is slower and more deliberate, performs more complex tasks like solving calculus problems. This system is also engaged when we need to focus our attention, make deliberate choices, or think critically.

Understanding the two systems helps us appreciate the role of heuristics in decision making. System 1, characterized by quick, automatic thinking, often relies on heuristics to make decisions with minimal cognitive effort. In contrast, system 2 requires slower, more deliberate thought. It is this system that allows us to override the automatic responses of system 1 when necessary, and engage in more rational, considered decision making.

System 1 thinking is often referred to as our intuitive system. It runs smoothly in the background, like an efficient and unobtrusive stagehand, away from the spotlight, making sure things are going as they should.

Interestingly, even when we believe we are making rational decisions, System 1 still impacts on our choices. This is because our beliefs and biases, which are deeply ingrained in our System 1 thinking and part of the mental shortcuts it employs, can subtly sway our decision-making process. This can occur even when we are consciously trying to think more slowly and more deliberately.

System 1 and System 2 thinking interact in a dual process. In any decision-making scenario, both systems are at play. System 1 provides quick, intuitive responses, while System 2 checks these responses for errors and tries to make adjustments when necessary. This dual process allows us to balance speed and accuracy in our decision making.

Since the introduction of the term ‘heuristics’ in cognitive psychology, numerous cognitive shortcuts have been explored and classified by experts. These play a central role in shaping our quick judgments, especially when overwhelmed with information.

Some heuristics are rooted in formal models, permitting mathematical proofs and algorithms. In contrast, informal ones are more like general rules of thumb guiding our decision-making processes.

Yet, it's essential to view heuristics beyond mere cognitive biases. Evolutionary psychologists highlight their adaptive value. For instance, German psychologist Gerd Gigerenzer coined the term ‘adaptive toolbox’. He posited that heuristics aren't always secondary to deliberate thinking. In many contexts, they offer effective, efficient guidance, steering us towards satisfactory outcomes without exhaustive contemplation.

Quick thinking is paramount in the fast-paced environment of a hospital’s emergency department. Here, medical practitioners do not have the luxury of time. They cannot question patients at length or run all possible tests on patients. Instead, they use whatever information is at hand to go down a path of questioning and, ultimately, to decide what must be done.

Doctors might go down a series of yes-no questions to eliminate likely options. Is the patient’s heart rate stable? If it is not, then run these tests. If it is, then is the patient running a fever? If they are, administer these drugs. If they aren't, then check for this other thing instead.

This kind of decision-making process uses a heuristic model called fast and frugal trees (FFTs). Essentially, FFTs use binary questions answered sequentially to reach a decision with minimal time and effort. Where time is a limited resource – emergency room triage, military operations, and customer relations – FFTs are an important tool. Like most heuristics, FFTs don’t always produce the most accurate or optimal decisions, but their efficiency and ease of use is vital in these contexts.

The availability heuristic is a mental shortcut that involves making decisions based on information that is most readily available in our memory. This heuristic operates on the notion that if something can be recalled, it must be important – or at least more important than alternatives that are not as readily recalled.

The availability heuristic can significantly influence our perceptions and decisions. For instance, many people's fear of flying can be attributed to this heuristic. They overestimate the chance of a plane crash because past incidents reported in the media have formed a strong impression in their memory, even if statistically, flying is much safer than other forms of transport.

This heuristic can lead to poor decision making. In policymaking, for example, an overemphasis on recent events that happen to be top of mind can lead to unnecessarily prioritizing​ certain matters over other more important or urgent concerns.

The use of heuristics can be seen as a rational response to humans’ limited information processing capabilities. Given the vast amount of information we encounter and the decisions we have to make on a daily basis, heuristics serve as practical tools that allow us to function effectively.

However, while heuristics are efficient, they do not always lead to the most rational or optimal decisions. Because they simplify complex problems, they also often ignore certain details and nuances that could be crucial. Thus, relying on heuristics can sometimes lead to errors or biases in our decision making.

Heuristics can also lead to systematic errors in thinking, what psychologists call cognitive biases. These biases can distort our perception of reality, leading us to make irrational decisions. These decisions will ultimately affect us and the people around us. Thus, while heuristics are practical tools, they carry limitations and present potential pitfalls.