Thinking, Fast and Slow
My main aim here is to present a view of how the mind works that draws on recent
developments in cognitive and social psychology.
Skill and heuristics are alternative sources of intuitive judgments and choices.
“The situation has provided a cue; this cue has given the expert access to information stored in memory, and the information provides the answer. Intuition is nothing more and nothing less than recognition.”
Valid intuitions develop when experts have learned to recognize familiar elements in a new situation and to act in a manner that is appropriate to it.
An important advance is that emotion now looms much larger in our understanding of intuitive judgments and choices than it did in the past. The executive’s decision would today be described as an example of the affect heuristic, where judgments and decisions are guided directly by feelings of liking and disliking, with little deliberation or reasoning.
If the individual has relevant expertise, she will recognize the situation.
This is the essence of intuitive heuristics: when faced with a difficult question, we often answer an easier one instead, usually without noticing the substitution.
I describe mental life by the metaphor of two agents, called System 1 and System 2, which respectively produce fast and slow thinking.
I attempt to give a sense of the complexity and richness of the automatic and often unconscious processes that underlie intuitive thinking, and of how these automatic processes explain the heuristics of judgment.
[I will] introduce a language for thinking and talking about the mind.
Why is it so difficult for us to think statistically?
We are prone to overestimate how much we understand about the world and to underestimate the role of chance in events. Overconfidence is fed by the illusory certainty of hindsight.
I deal with the unfortunate tendency to treat problems in isolation, and with framing effects, where decisions are shaped by inconsequential features of choice problems.
The experiencing self and the remembering self ... do not have the same interests.
What makes the experiencing self happy is not quite the same as what satisfies the remembering self.
You experienced slow thinking as you proceeded through a sequence of steps. You first retrieved from memory the cognitive program for multiplication that you learned in school, then you implemented it. Carrying out the computation was a strain. You felt the burden of holding much material in memory, as you needed to keep track of where you were and of where you were going, while holding on to the intermediate result.
work: deliberate, effortful, and orderly—a prototype of slow thinking.
System 1 operates automatically and quickly, with little or no effort and no sense of voluntary control. System allocates attention to the effortful mental activities that demand it, including complex computations. The operations of System are often associated with the subjective experience of agency, choice, and concentration.
I describe System 1 as effortlessly originating impressions and feelings that are the main sources of the explicit beliefs and deliberate choices of System .
We are born prepared to perceive the world around us, recognize objects, orient attention, avoid losses, and fear spiders. Other mental activities become fast and automatic through prolonged practice.
The knowledge is stored in memory and accessed without intention and without effort.
The highly diverse operations of System have one feature in common: they require attention and are disrupted when attention is drawn away.
we can be blind to the obvious, and we are also blind to our blindness.
In summary, most of what you (your System 1 ) think and do originates in your System 1, but System 2 takes over when things get difficult, and it normally has the last word.
System 1 is generally very good at what it does: its models of familiar situations are accurate, its short-term predictions are usually accurate as well, and its initial reactions to challenges are swift and generally appropriate. System 1 has biases, however, systematic errors that it is prone to make in specified circumstances.
It sometimes answers easier questions than the one it was asked, and it has little understanding of logic and statistics.
One further limitation of System 1 is that it cannot be turned off.
Conflict between an automatic reaction and an intention to control it is common in our lives.
Not all illusions are visual. There are illusions of thought, which we call cognitive illusions.
Because System 1 operates automatically and cannot be turned off at will, errors of intuitive thought are often difficult to prevent. Biases cannot always be avoided, because System 1 may have no clue to the error.
. As a way to live your life, however, continuous vigilance is not necessarily good, and it is certainly impractical. Constantly questioning our own thinking would be impossibly tedious, and System is much too slow and inefficient to serve as a substitute for System in making routine decisions.
recognize situations in which mistakes are likely and try harder to avoid significant mistakes when the stakes are high.
it is easier to recognize other people’s mistakes than our own.
System 1 and System 2 are so central to the story I tell in this book that I must make it absolutely clear that they are fictitious characters.
anything that occupies your working memory reduces your ability to think.
the response to mental effort is distinct from emotional arousal.
System 2 is the only one that can follow rules, compare objects on several attributes, and make deliberate choices between options.
System 1 detects simple relations (“they are all alike,” “the son is much taller than the father”) and excels at integrating information about one thing, but it does not deal with multiple distinct topics at once, nor is it adept at using purely statistical information.
A crucial capability of System 2 is the adoption of “task sets”: it can program memory to obey an instruction that overrides habitual responses.
One of the significant discoveries of cognitive psychologists in recent decades is that switching from one task to another is effortful, especially under time pressure.
We normally avoid mental overload by dividing our tasks into multiple easy steps, committing intermediate results to long-term memory or to paper rather than to an easily overloaded working memory.
The psychologist Mihaly Csikszentmihalyi (pronounced six-cent-mihaly) has done more than anyone else to study this state of effortless attending, and the name he proposed for it, flow, has become part of the language.
Several psychological studies have shown that people who are simultaneously challenged by a demanding cognitive task and by a temptation are more likely to yield to the temptation.
People who are cognitively busy are also more likely to make selfish choices, use sexist language, and make superficial judgments in social situations.
cognitive load is not the only cause of weakened self-control.
The self-control of morning people is impaired at night; the reverse is true of night people.
Too much concern about how well one is doing in a task sometimes disrupts performance by loading
short-term memory with pointless anxious thoughts.
controlling thoughts and behaviors is one of the tasks that System 2 performs.
How to Write a Persuasive Message
The general principle is that anything you can do to reduce cognitive strain will help, so you should first maximize legibility.
If you use color, you are more likely to be believed if your text is printed in bright blue or red than in middling shades of green, yellow, or pale blue.
If you care about being thought credible and intelligent, do not use complex language where simpler language will do.
In addition to making your message simple, try to make it memorable. Put your ideas in verse if you can; they will be more likely to be taken as truth.
if you quote a source, choose one with a name that is easy to pronounce.
System 2 is lazy and that mental effort is aversive. If possible, the recipients of your message want to stay away from anything that reminds them of effort, including a source with a complicated name.
What psychologists do believe is that all of us live much of our life guided by the impressions of System 1—and we often do not know the source of these impressions.
Performance was better with the bad font. Cognitive strain, whatever its source, mobilizes System 2, which is more likely to reject the intuitive answer suggested by System 1.