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Thinking fast and slow by Daniel Kahneman

System One and System Two

  • Kahneman roughly splits the way we think in to two different systems.
  • They are ways and attributes of how we think, and are not strictly defined by a specific place, different from the traditional 'left brain-right brain' dichotomy
  • Because they're easy to remember the two ways of thinkning are called system 1 and system 2 because they are short
  • System 1 is involved in intuitive responses and actions.
  • System 2 is involved with cognitive and throughtful processes.
  • Judging emotions of a person's face is a system 1 action
  • Long form multiplication, like 345x288 is a system 2 action
  • 2+2 = 4 is a system 1 action
  • Reversing in to a small parking space is a system 2 action.
  • Some system 2 actions can be incorporated in to system 1 actions, through repeated doing.
  • Doing system 1 and system 2 actions can be very difficult or impossible, depending on the task

Attention and effort

  • Kahneman outlines the relation between mental effort and system 2
  • Generaly we will prefer to stay out of system 2 for as long as possible.
  • He uses the Add-1 and Add-3 tasks as examples of maximum effort in system 2
  • Add - 3 is a game where your'e adding 3 digits up on a string of four digits under time pressure.
  • Pupils will dialate and the brain gets aroused when it has to work hard
  • As soon as you have solved the problem or given up, your pupils will go back to normal
  • Kahneman talks about how the brain can start to commit certain actions which are quite difficult in to learned behavious, such as counting the number of f's in a page.
  • This pattern becomes harder as you try and switch to another equally hard or harder task
  • The gorrilla experiment, where people are asked to count the number of passes between a team, shows that when cognitive effort increases, system 2 begins to prioritise attention to the most important task, and will ignore the gorrila.
  • In the same way system 1 will often take action, without you even being consiously aware of it(hitting the breaks in a car accident)

The Lazy Controller

  • Kahneman gives an example of walking and thinkning
  • At a certain pace it's easy to think, at another much harder
  • There is only a certain amount of things we can do at any given time.
  • Kahnemen references to some studies on the idea of ego depletion
  • Kahneman references the work done on flow, showing that focus can be maintained in a certain area, without any effort, because the task itself is enjoyable enough to be seen as effortless.
  • Ego depletion doesnt always happen. It is also not in the same part of the brain as cognitive strain. → Just because you're being cognitively strained doesnt mean your ego is being depleted.
  • Ego depletion is the force that causes people who have already withheld from temptation to give in to more temptation
  • Bat and ball question is shown as well as roses and flowers example.
  • Kahneman shows the idea of questions which have an intuitive but incorrect answer to them
  • System 2 can in some people, and at some times, be quite lazy. It delays thinkning or checking that a problem is correct
  • Some references made to the marshmallow test, and the outcomes of the children years later showing that chidlren who could delay, we're usually more intelligent.
  • Also some references made to the idea that focussing on a task, can improve intelligence in children. → Does this translate to adults?
  • Some final examples on people who say or do things without checking to see if they're correct, or the right thing to do.
  • "Blurting out the first thing that comes to your mind" → Lazy system 2.