Donna's Reviews > Thinking, Fast and Slow

** spoiler alert ** This book is a rich narrative of all the phases of Kahneman's studies with Tversky and studies after Tversky died. The insights of this book challenges the way we see ourselves. How we understand ourselves and the world are prone to exaggeration, that we must be alert to the perils of our overconfidence. Basically, what he's saying is that we, humans, are fundamentally irrational because of our cognitive biases, fallacies, and illusions. We are not generally rational as what we were led to believe by orthodox social scientists. We may be “healthy most of the time, and most of our judgments and actions are appropriate most of the time” but the studies he did with Tversky discovered “systematic errors in the thinking of normal people”. These errors they found do not arise from the “corrupting effects of emotion” but rather built into the cognitive machinery.

These conclusions on errors, Kahneman explains, are products of a 2-system reasoning in the brain. System 1 is our fast, intuitive, and unconscious mode. System 2 is our slow, analytical, and conscious mode. System 1 is what effortlessly finishes phrases/sentences (“bread and...”) and System 2 is what fills out a tax form with a lot of effort. System 1 produces a quick draft of reality through association and metaphor while System 2 arrives at reasoned beliefs and choices through drawing on ideas. System 1 drafts while System 2 edits. Although System 2 is rational, it is also lazy. Instead of slowing down and analyzing, System 2 easily tires and just accepts the easy but unreliable interpretation of the world that System 1 feeds into it. Even though theoretically, System 2 should be the boss, it is System 1 who is the hero. Especially when you're in a happy mood, System 2 is idle. To be clear, System 1 and 2 are not separate aspects in the brain with distinct personalities, they are complex processes defined as narratives to easily explain the weirdness that is the human brain.

To illustrate, Kahneman recalls the most controversial experiments he and Tversky did. It's called “the Linda problem”. In this experiment, participants were told about Linda, a single, outspoken, and very bright imaginary young woman, who as a student, was deeply concerned with discrimination and social justice issues. After, they were asked which was more probable: (1) Linda is a bank teller. Or (2) Linda is a bank teller and is active in the feminist movement. Most of the responses they got was that (2) was more probable, which is an obvious violation of the probability laws: adding a detail lowers the probability. Even in Stanford’s Graduate School of Business, 85% flunked the Linda problem. What happened here then?

When an easy question is substituted with a more difficult one, our thinking panics and bases its reasoning with an intuitive one with the System 2 lazily endorsing a heuristic answer without it processing logically. This is the source of the biases that infect our thinking. These errors in thinking, even if identified, are hard to overcome and Kahneman goes on to say that there's no evidence that it would make our lives better which now raises the fundamental question: What is the point of rationality? In this point, Kahneman leaves out discussing philosophically the nature of rationality but instead delves into what might be taken to be its goal: happiness. When Kahneman started investigating happiness, initially most of the researches that time relied on questions asking how satisfied people are with their lives as a whole – these assessments were retrospective and relied heavily on memory. Kahneman alternatively though that maybe, actual experience of pain pr pleasure can be “sampled from moment to moment and summed up over time”. He called this “experienced” well-being versus the “remembered” well-being. What he found out surprised him. The happiness that the experiencing self experiences is not what the remembering self remembers. The remembering self rates an experience by the “peak level of pain or pleasure” in the course of the experience and how it ends and does not care about how long an experience lasts. What he found out is that it's the remembering self that makes the decision and not the experiencing self. This idea is actually supported by a study by Rafael Malach at the Weizmann Institute in Israel. Their study has shown that when a person in absorbed in an experience, parts of the brain associated with self-consciousness shut down – it seems like the self disappears.

What I am taking away from this book is to deliberately think. This is especially valuable in the current time where information is excessive in social media. Think about what things to absorb and think to analyze the information before absorbing them.