Thinking, fast and slow
Source: Kahneman
Chapter 1: the characters of the story
There are two ways of thinking, Kahneman calls them system 1 and system 2.
System 1 = operates automatically and quickly, with little or no effort and no sense of voluntary
control. System 1 can make associations between ideas (capital of France?) and has the skills such to
read and interpret subtle body language. Knowledge is stored in our memory and can be quickly
recalled and explored. Sometimes system 1 can create biases, systemic mistakes created in specific
situations.
System 2 = allocates attention to the effortful mental activities that demand it, including complex
computations. The operations of system 2 are often associated with the subjective experience of
agency, choice, and concentration. The different processes of system 2 have one thing in common,
namely that they require attention and are interrupted if our attention goes to something else. For
these tasks full attention is necessary and it is not possible to accomplish the tasks without full
attention. System 2 has some ability to change the way System 1 works, by programming the
normally automatic functions of attention and memory. You dispose of a limited budget of attention
that you can allocate to activities, and if you try to go beyond your budget, you will fail. It is the mark
of effortful activities that they interfere with each other, which is why it is difficult or impossible to
conduct several at once (reken maar eens een rekensom uit in druk verkeer).
Cooperation between system 1 and 2
Systems 1 and 2 are both active whenever we are awake. System 1 runs automatically and System 2
is normally in a comfortable low-effort mode, in which only a fraction of its capacity is engaged.
The division of labor between System 1 and System 2 is highly efficient: it minimizes effort and
optimizes performance.
- System 1 continuously generates suggestions for System 2: impressions, intuitions,
intentions, and feelings. If endorsed by System 2, impressions and intuitions turn into beliefs,
and impulses turn into voluntary actions. When all goes smoothly, which is most of the time,
System 2 adopts the suggestions of System 1 with little or no modification. You generally
believe your impressions and act on your desires, and that is fine—usually.
- When System 1 runs into difficulty, it calls on System 2 to support more detailed and specific
processing that may solve the problem of the moment. System 2 is mobilized when a
question arises for which System 1 does not offer an answer.
- Conflicts: one of the tasks of System 2 is to overcome the impulses of System 1. In other
words, System 2 is in charge of self-control. So, sometimes system 1 and 2 are in conflict and
system 2 has to suppress the automatic reactions of system 1 (oefening met lettergrootte
van de woorden groot/klein benoemen).
- Illusions: 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 2
may have no clue to the error. Even when cues to likely errors are available, errors can be
prevented only by the enhanced monitoring and effortful activity of System 2. 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 2 is much too slow and inefficient to serve as a substitute for System 1 in making
routine decisions. The best we can do is a compromise: learn to recognize situations in which
mistakes are likely and try harder to avoid significant mistakes when the stakes are high
,Chapter 3: The lazy controller
Law of least effort = people are trying to avoid effort
Flow = “a state of effortless concentration so deep that they lose their sense of time, of themselves,
of their problems,” and their descriptions of the joy of that state are so compelling that it is called an
“optimal experience.” Flow neatly separates the two forms of effort: concentration on the task and
the deliberate control of attention. In a state of flow, maintaining focused attention on these
absorbing activities requires no exertion of self- control, thereby freeing resources to be directed to
the task at hand.
The busy and depleted system 2:
Both self-control and cognitive effort are forms of mental work. 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. System 1 has more influence on behavior
when System 2 is busy, and it has a sweet tooth. People who are cognitively busy are also more likely
to make selfish choices, use sexist language, and make superficial judgments in social situations.
So cognitive load causes weakened self-control
The conclusion is straightforward: self-control requires attention and effort. Another way of saying
this is that controlling thoughts and behaviors is one of the tasks that System 2 performs.
Ego depletion = an effort of will or self- control is tiring; if you have had to force yourself to do
something, you are less willing or less able to exert self-control when the next challenge comes
around.
activities that impose high demands on System 2 require self-control, and the exertion of
self-control is depleting and unpleasant. Unlike cognitive load, ego depletion is at least in
part a loss of motivation. After exerting self-control in one task, you do not feel like making
an effort in another, although you could do it if you really had to.
The effects of ego depletion could be undone by ingesting glucose, because the nervous
system consumes more glucose than most other parts of the body, and effortful mental
activity appears to be especially expensive in the currency of glucose.
The lazy system 2
The extent of deliberate checking and search is a characteristic of System 2, which varies among
individuals. Those who avoid the sin of intellectual sloth could be called “engaged.” They are more
alert, more intellectually active, less willing to be satisfied with superficially attractive answers, more
skeptical about their intuitions. The psychologist Keith Stanovich would call them more rational.
Intelligence, control and rationality
If people were ranked by their self-control and by their cognitive aptitude, would individuals have
similar positions in the two rankings?
More self-control at young age, causes more intelligence. Self-control might also be genetically
determined. Also there was a close connection between the children’s ability to control their
attention and their ability to control their emotions. People with a lazy system 2 are impulsive,
impatient, and keen to receive immediate gratification.
System 1 is impulsive and intuitive; System 2 is capable of reasoning, and it is cautious, but at least
for some people it is also lazy. We recognize related differences among individuals: some people are
more like their System 2; others are closer to their System 1.
Stanovich made a distinction between two parts of System 2—indeed, the distinction is so sharp that
he calls them separate “minds.” One of these minds (he calls it algorithmic) deals with slow thinking
and demanding computation. Some people are better than others in these tasks of brain power—
, they are the individuals who excel in intelligence tests and are able to switch from one task to
another quickly and efficiently. However, Stanovich argues that high intelligence does not make
people immune to biases. Another ability is involved, which he labels rationality. Stanovich’s concept
of a rational person is similar to what I earlier labeled “engaged.” The core of his argument is that
rationality should be distinguished from intelligence. In his view, superficial or “lazy” thinking is a
flaw in the reflective mind, a failure of rationality.
Chapter 25: Bernoulli’s errors
Behavioral economist Richard Thaler divided persons into Econs and Humans. In which Econs are
agents of the economic theory who are rational, selfish, and their tastes do not change. Unlike Econs,
the Humans that psychologists know have a System 1. Their view of the world is limited by the
information that is available at a given moment (WYSIATI), and therefore they cannot be as
consistent and logical as Econs. They are sometimes generous and often willing to contribute to the
group to which they are attached. And they often have little idea of what they will like next year or
even tomorrow.
Expected utility theory from Bernoulli = the foundation of the rational-agent model and is to this day
the most important theory in the social sciences. Expected utility theory was not intended as a
psychological model; it was a logic of choice, based on elementary rules (axioms) of rationality. Tries
to understand how risky decisions are made by humans.
Prospect theory = closely modeled on expected utility theory but departed from it by the fact that
the prospect theory was purely descriptive, and its goal was to document and explain systematic
violations of the axioms of rationality in choices between gambles.
Bernoulli’s error:
Prior to Bernoulli, mathematicians had assumed that gambles are assessed by their expected value: a
weighted average of the possible outcomes, where each outcome is weighted by its probability.
Bernoulli observed that most people dislike risk (the chance of receiving the lowest possible
outcome), and if they are offered a choice between a gamble and an amount equal to its expected
value they will pick the sure thing. In fact a risk-averse decision maker will choose a sure thing that is
less than expected value, in effect paying a premium to avoid the uncertainty. One hundred years
before Fechner, Bernoulli invented psychophysics to explain this aversion to risk. His idea was
straightforward: people’s choices are based not on dollar values but on the psychological values of
outcomes, their utilities. The psychological value of a gamble is therefore not the weighted average
of its possible dollar outcomes; it is the average of the utilities of these outcomes, each weighted by
its probability. Bernoulli’s insight was that a decision maker with diminishing marginal utility for
wealth (de hoeveelheid die je ervoor terug krijgt wordt steeds minder dus omgekeerd exponentieel)
will be risk averse. This is called moral expectation.
The longevity of the theory is all the more remarkable because it is seriously flawed. The errors of a
theory are rarely found in what it asserts explicitly; they hide in what it ignores or tacitly assumes.
The theory must be wrong because it only looks at the utility of the outcome, instead of the change
of the outcome. (Bijv: gister had Jack 1 miljoen en had Jill 9 miljoen, vandaag heeft Jack 5 miljoen en
Jill 5 miljoen. Volgens Bernoulli’s theory zouden ze even blij zijn, hoewel Jill erop achteruit is gegaan.
Zijn theorie kijkt niet naar de verandering).
Furtermore, the theory fails because it does not allow for the different reference points. The theory
does not look at the background of people. (Bijv: als Laura 4 miljoen bezit en ik 1 miljoen. We krijgen
beide de volgende keuze: met zekerheid 2 miljoen te krijgen of 50/50 kans op 1 miljoen of kans op 4
miljoen. Voor mij is met zekerheid 2 miljoen krijgen een goede deal, hoewel Laura hiermee 2 miljoen