System 1 and System 2 explained

“System 1 operates automatically and quickly, with little or no effort and no sense of voluntary control. System 2 allocates attention to the effortful mental activities that demand it, including complex computations.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 1, The Characters of the Story

Kahneman's own English, the paired definitions in chapter 1. He presents them as characters, a way to talk about two modes, not as two little people in the head.

System 1 is fast, automatic, and does not feel like a choice. System 2 is the attention you spend when the work is effortful, including calculation. The usual reading takes the pair as a story that organises the later biases, not as brain anatomy. A competing reading makes System 1 the villain and System 2 the hero. He thinks System 2 is often lazy and endorses what System 1 already offered. The sentences are chapter 1 of Thinking, Fast and Slow. The names are a convenience. The difference in effort is the point. Speed is not by itself an error.

“I will use a cumbersome abbreviation for it: WYSIATI, which stands for what you see is all there is.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 7, A Machine for Jumping to Conclusions

His abbreviation and his gloss, in chapter 7. 'Biases' is not a theme in this library's list, so the card is filed under mind and knowledge. The sentence is his.

WYSIATI names the habit of jumping to a conclusion on the evidence in hand, as if the evidence you do not have were not missing. The usual reading is that the story feels complete because absent facts do not announce themselves. A competing reading treats the abbreviation as advice to decide quickly on purpose. He is diagnosing a feature of intuitive thinking that he says comes up all through the book. The sentence is chapter 7. Cumbersome is his joke about the abbreviation. The content is that unseen information has no weight inside the story System 1 has already built.

“It is the consistency of the information that matters for a good story, not its completeness. Indeed, you will often find that knowing little makes it easier to fit everything you know into a coherent pattern.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 7, A Machine for Jumping to Conclusions, p. 87

His English. Page 87 of the 2011 Farrar, Straus and Giroux edition. Other printings can move the page. The chapter title is the stable citation.

A good story, in this technical sense, is a consistent one, and consistency is easier when you know less. The mainstream reading is a warning: the pleasure of a pattern is not evidence that the pattern used enough of the world. A competing reading admires the thin story as elegant and stops, which is the mistake the chapter describes. He says you will often find that knowing little helps the fit. The sentences are chapter 7, with WYSIATI. Completeness is the standard he says the mind does not use. Coherence is the standard it does.

“Confidence is a feeling, which reflects the coherence of the information and the cognitive ease of processing it.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 20, The Illusion of Validity, p. 212

His English. Page 212 of the 2011 Farrar, Straus and Giroux edition, in the chapter on the illusion of validity. He adds that declarations of high confidence tell you a coherent story has been built, not that the story is true.

Confidence is not a quiet calculation of how likely you are to be right. It is a feeling, fed by how well the information hangs together and how easily it is processed. The usual reading connects the sentence to WYSIATI: a coherent fragment feels certain. A competing reading still treats a confident expert as someone who has seen more, which is sometimes true and not what the feeling measures. The sentence is chapter 20. Cognitive ease is the fluency of the thought. Fluency is not a census of the evidence.

“Amos and I coined the term planning fallacy to describe plans and forecasts that are unrealistically close to best-case scenarios.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 23, The Outside View

His English in chapter 23, where he retells the curriculum project that taught him the outside view. He and Tversky had named the fallacy earlier. This sentence is the book's definition. No page is pinned here because editions shift; the chapter is stable.

The planning fallacy is a forecast stuck near the best case. They coined the name for that pattern, and for the improvement that comes from looking at similar cases rather than at the story of this one. The usual reading is the inside view against the outside view: your plan in your head, versus the record of plans like it. A competing reading thinks the fallacy is mere pessimism about all plans. He is not against planning. He is against a best case that has not met a base rate. The sentence is chapter 23. The curriculum story in that chapter is the example. The definition is the sentence.

“Nothing in life is as important as you think it is when you are thinking about it.”

Daniel Kahneman · Thinking, Fast and Slow (2011), chapter 38, Thinking about Life, p. 402

His English, the focusing illusion as he states it at the end of chapter 38. Page 402 of the 2011 Farrar, Straus and Giroux edition. The 'when' is his; posters sometimes print 'while'.

Whatever you are attending to swells. Nothing, he says, is as important as you think it is while it has your attention. The usual reading calls this the focusing illusion: the focal item crowds out the rest of a life. A competing reading hears that nothing matters, which would cancel the book. He is talking about a bias in judgement, especially when people predict how an event will change their happiness. The sentence is chapter 38. Attention is the magnifier. Importance is what the magnifier counterfeits.