# [[vn-2025-06-26 Understanding System 1 and System 2 thinking]] Date: 2025-06-26 ## Main points - Two systems of thinking: System 1 and System 2. - System 1 is fast thinking; System 2 is slow thinking. - System 1 happens involuntarily and instinctively. - System 1 is based on exposure to patterns, not systematic. - System 2 is systematic, methodical, and logical. - System 2 requires attention and is used for higher-level reasoning. - System 2 requires more cognitive attention. - System 1 operates most of the time, answering simpler questions. - System 1 makes suggestions which System 2 may accept. - System 2 is called on consciously and assesses System 1's suggestions. - System 2 can solidify intuitions into beliefs and habits. - System 2 can make mistakes and focus on the wrong things. ## Transcript First chapter of Thinking Fast and Slow by Daniel Kahneman. This chapter is about the two systems of thinking, System 1 and System 2. Personally, I call System 1 fast thinking and System 2 slow thinking. But he had a note about how it was intentional to use the just Systems 1 and 2 numbers to identify them, and that's so that we don't form any other biases on them, like we're not tempted to make one a villain, for example, because neither of them is; they're both really important. System 1 is the system that is involved when someone surprises you, or it's basically involuntary, or it can sometimes be voluntary, sometimes not, but it happens immediately, instinctively. This is our intuition that knows things, that makes leaps and makes decisions or wants to make decisions or actions based on things that it has learned before. But this learning is not systematic. It's just being exposed to patterns over and over and then suddenly reacting in a way that without even really puzzling out the logic. It is not systematic. System 2 is systematic. System 2 is methodical and logical. And it is what we call on when we need to divide numbers or we need to do mathematics or give someone our phone numbers or do any sort of higher-level reasoning. Now, we might be tempted to think that this is the more rational, more trustworthy of the two, the mode that we should operate in all the time. But the reality is that we can't because attention is limited. Both System 1 and 2 require attention, but System 2 definitely requires more, requires a surge of cognitive attention. So what normally happens is System 1 is the mode that we operate on almost every day and for most times. System 1 answers questions. So when there's a complex question, System 1 answers a similar but not, but different, simpler question. And most of the time it works, or it appears to. Every now and then it will make these suggestions of what it thinks to System 2. And most of the time, System 2 is not engaged or is not needed. So System 2 just accepts those suggestions. But every now and then we explicitly consciously call on System 2, and then System 2 must decide whether it actually does accept what System 1 thinks. If it does, then what was like a fleeting intuitive belief now or fleeting intuition now becomes a belief. And over time, if that belief becomes solidified into a pattern, then it is a habit, a part of us, of our behavior. System 2 can make mistakes too, though. System 2 takes a very long time because it requires attention, and sometimes it focuses on the wrong things because you have to direct your attention. So sometimes that attention doesn't get to the place where we want it to go to. And that's when System 1 can come in and be like, well, actually, that's not what we need to be looking at. So System 2 can also be led astray. ![[MoDBoE86.mp3]] ## Related Notes - [[vn-2025-06-26 Remediations before ghosting and the role of doubt]] - [[vn-2025-06-26 Connecting circuit breakers and ghosts in engineering]]