Psychological Self-Help

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of your own false reasoning and correct it. An additional corrective
step might be to explore your history to gain some insight into the
original experiences that now prompts the experience-based mind to
think in these stressful, unhelpful ways. 
Also included in this list are fallacious, misleading strategies used
by debaters to persuade the opponent of their viewpoint. These are
ways we get fooled and fool ourselves too. 
a. Over-generalizing and common mental errors --coming to
a conclusion without enough supporting data. We hear about many
teenagers using drugs and alcohol, then conclude that the younger
generation is going "to pot." We hear that many black men desert
their families and that many black women go on welfare, then assume
(pre-judge) that most black men are sexually irresponsible and most
black women want babies, not work. On a more personal level, the
next teenager or black we meet we may suspect of being "high" or
unfaithful. We are turned down by two people for a date, then
conclude "no woman/man will go with me." We have found school
uninteresting and conclude that we will never like to study. We find
two red spots on our nose and conclude we have cancer (also called
Anecdotal evidence is another example of taking one incident
and assuming it proves a larger principle. Example: "I had a case once
in which the marital problems disappeared as soon as the woman
learned to have orgasms, so I do sex therapy with all couples." This
thinking won't surprise anyone, but there is a troubling tendency to
give more weight to a single person's opinion or experience--especially
if the information is given to us face to face--than to a statistical
summary of many people's opinions or experience. One person's story
is not an accurate sample! Frankly, there is evidence that we don't
read tables very well, e.g. we attend more to what a diagnostic sign
(like a depression score) is related to, than we do to what the absence
of the sign is related to. Let's look at an example. 
The situation may become a little complicated, however. Suppose
you had a psychological test that you knew was 95% accurate in
detecting the 5% of people who are depressed in a certain way.
Further suppose that 35% of non-depressed people are misdiagnosed
as being depressed by this test. If a friend of yours got a high
depression score on this test, what are the chances he/she really is
depressed? What do you think? The majority of people will say 65% or
higher. Actually the chances are only 13%! The test is very good at
detecting the 5% who are depressed (and we notice this score), but
the 35% "false positives" is terrible (but not noticed), i.e. the test is
misdiagnosing over 1/3rd of the remaining 95% of people as being
depressed when they are not. But unless we guard against ignoring
the base rates (the ratio of non-depressed to depressed persons in the
population), we will, in this and similar cases, error in the direction of
over-emphasizing the importance of the high test score. Guard against
over-generalizing from one "sign." One swallow doesn't make a
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