Conformation Bias: a blanket expression for a family of biases, a wide variety of
ways in which beliefs, expectations, or emotional commitments regarding a
hypothesis can lead to its seeming more highly confirmed than the evidence really
o Ex. Seeing resemblances between a newborn and it's parents
Are extremely common, and can be manifested in different ways:
o Biases toward evidence supporting the belief in question
Naturally one way of inflating the evidence supporting a belief
already held is to go about looking for evidence in a way that is
particularly likely to find results favourable to the belief.
This amounts to giving a "free pass" to seemingly supportive
evidence by not really questioning favourable evidence or not
making the effort to explore contradictions between various
o Biases toward evidence undermining a belief.
Evidential Neglect: a bias against some bit of countervailing
information may be manifest in the way we hastily dismiss or
disregard it, without much regard for its potential virtues.
Disproportianate criticism: Sometimes evidence that undermines
'B' reveives a biased treatment of just the opposite sort. Rather than
ignoring or dismissing countervailing evidence, we may often subject
it to a harsh and critical examination.
Metacognition: the theme that critical thinking begins at home.
Self-fulfilling prophecies: predictions that come true not simply because the
predictor foresees how events will unfold, but because the prediction itself has an
effect on how things unfold.
o Ex: a palm reader tells his team will win against a better team, now he has
the confidence to play better and wins the game.
o A prediction is just the sort of thing that can introduce a powerful
confirmation bias at the levels of perception, cognition, and memory.
o The fact that a positive prediction was made at all would cause the subject to
notice his positive actions as positive and not dwell on the negative actions.
o We don't need an expectation for the effect to occur - just salience (ie.
o Confirming instances have a much stronger tendency to remind people of the
rule/theory/belef/prophecy than non-confirming instances
When you expect (consciously or not) some outcome, this can create a
Framing Effects: influences brought on by the way a situation is described to think
of a situation differently.
Repetition: one important factor determining a subject's likelihood of ranking a
statement as true is often the statement has been repeated to the subject in the
If we hear something repeatedly, it is easier for us to consider it as truthful or
at least reasonable.
Search Methods and Confirmation Bias: A way of artificially inflated evidence
supporting 'B' is to go about looking for evidence in a way that is particularly likely
to find results favourable to the belief.
Structural Biases: situations (including experimental situations) that have a
structure that preferentially yields confirming evidence.
Social Cognition: the existence of other people in a reasoning context, and the
nature of our relations with them, apply our judgements and inferences in two
1. Reasoning about other people
2. Reasoning influenced by them
Thinking in group contexts: the number and kind of people around us are a major
influence on the way we reason, problem solve and make decisions.
o They are sources of much of our information
o Much are reasoning is about them or at least affected by their presence.
o If we wish to reason well in group contexts over the long term, we must be
aware of pitfalls - with our reasoning about, and in the presence of, other
people tends to be flawed in a predictable set of ways - so we can
metacognitively monitor ourselves and the situation to know when a red flag or
caution is required.
o In many social contexts there are powerful pressures that work to prevent
challenging and debunking dubious beliefs, or even known falsehoods,
resulting in propositions that continue to circulate despite being unjustifiable.
o Common forms of poor reasoning about others have a few shared
• Optimistic assessment of ourselves
• Idealized/oversimplified theorizing
• Over-emphasis on character rather than context
Fundamental Attribution Error: a bias in favour of explaining someone's situation
/behaviour in terms of their personality, character or dispositions while overlooking
explanations in terms of context, accidents or the environment more generally.
Reasoning about other people based on small samples of their behaviour is
therefore a red flag.
o The problem with reasoning from limited behaviour to deep personality traits
might be obvious on evidential grounds, but what we need to bear in mind is
how intuitively tempting we find such inferences in the social realm
A willingness to treat momentary behaviour as a "one-off" can help us form
more accurate impressions of the people around us. The False Polarization Effect: the tendency to overestimate two things - the extent
to which the views of other resemble the strongest or most stereotypical positions
of those sorts, and the differences between one's own view and the view of the
o Essentially the fundamental attribution error and the optimistic self
assessment working together.
o How to de-bias the FPE:
• Take a few minutes to consider why the opposite arguer has their
opinion, and try to see their side of things.
o FPE fallacy:
• Someone in the middle of two extreme opinions in an argument
believes they're view is reasonable because the arguers on either extreme
side disagree with what they're saying.
o How reasoning about others entrenches FPE:
• Beleiving that it's seen as an admission of weakness in our position, we
are unwilling to articulate our reservations about the stereotypical view to
those with whom we generally disagree.
• Believing that it's seen as wishy-washy, we are unwilling to articulate
our reservations about the stereotypical view to those whom we generally
Bandwagon: the tendency for our beliefs to shift toward the beliefs we take to be
widely held by those around us.
o When all or most people in a group are in agreement. It's much more difficult
to hold a dissenting view.
o Often what ties belief and expression - pressure against expression dissent
creates pressure against dissenting belief
o Example; religion
False Consensus Effect: the common tendency to overestimate the extent to which
others share our beliefs and attitudes.
o Example; when we believe t