Reason and Argument
Chapter 2
Critical Thinking
• Critical thinking involves awareness, practice,
and motivation.
• Often, how we think and what we think are
obstacles to be overcome for the sake of
critical thinking.
• Many of the things you believe may be false,
and many of the true things you believe, you
may believe for no good reason.
How we think:
• Certain facts about who we are and how we
make decisions and accept beliefs can hinder
our abilities to think critically.
• Recognizing and combatting these factors is a
big part of thinking critically.
Self-Interest
• There is nothing wrong with supporting a
claim that is in your interests, but a claim
requires more than being in your interest to
be supported.
• Excessive self-interest leads to rationalization,
wishful thinking, self-deception, and
manipulation by those who simply tell you
what you want to hear.
Confirmation Bias
• Aka ‘selective attention’ is a well-researched bias
in peoples’ reasoning.
• Once people form a theory or an opinion, they
tend to look only for or only notice evidence that
confirms their prior theory or opinion while
failing to notice evidence that denies prior theory
or opinion.
• Combatting confirmation bias requires a great
deal of attention and care. It requires a sustained
conscious effort to recognize and avoid it.
Confirmation Bias (continued)
• Bob thinks Steve is always rude to him, and
every time that Steve is rude to Bob, Bob
treats that as evidence for his opinion. When
Steve is not rude to Bob, Bob doesn’t notice
one way or the other. This is confirmation
bias. It may turn out that Steve is not rude to
Bob any more often than anyone else, or not
very much more often.
Group think
• Group think can take multiple forms:
– Peer pressure
– Appeals to Popularity
– Appeals to Common Practice
– Overvaluing group ideas
• Group think can be just as bad as excessive
self-interest.
What we think:
• Many of your beliefs are false.
• What follows are some very common beliefs
that often get in the way of being a good
critical thinker.
Relativism/subjectivism
• There are many kinds of relativism and
subjectivism, but the kinds that are a
hindrance to critical thinking are often
confused with the unobjectionable kinds.
• To be a good critical thinker, one must
recognize the difference between descriptive
relativism and normative relativism and also
the difference between subjective issues and
non-subjective issues.
Descriptive versus Normative
Relativism
Descriptive
• As a matter of fact different
people have different
opinions and beliefs.
• As a matter of fact, different
cultures have different
opinions and beliefs.
• The above is certainly true,
but trivial.
Normative
• Each opinion that an
individual or culture holds is
equally true or valuable.
• The above is certainly false,
and often confused with
the position at left.
Subjective versus Non-Subjective
Issues
Subjective
• Taste
• Aesthetic Issues
Non-Subjective
• Truth
• Morality
Subjective issues are issues
that everyone is fine with
letting everyone determine
for themselves. Substantive
disagreement isn’t possible
with genuinely subjective
issues.
Non-Subjective issues are not
simply matters of taste, and
are not determined arbitrarily.
Substantive disagreement is
possible with non-subjective
issues.
Excessive Skepticism
• It is one thing to entertain doubts about even
very strongly held beliefs. This is healthy.
• However, blowing some doubts out of
proportion (like Descartes) is a good way to be
a poor thinker.
• We may accept some claims even while not
being entirely certain about them, so long as
we have good enough reasons to do so.