
Motivated Numeracy and Enlightened Self-Government (2013) - evilsimon
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2319992
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ageofwant
Clever and informed people simply have better tools to defend their biases.
Auto-gaslighted high-intelligence individuals are more common (in my
experience) than not.

Intelligence is no defence against delusion, in fact its the other way around.

------
GregBuchholz
I was really hoping to find a reference to Jaynes' "Probability Theory: The
Logic of Science" at the end of the paper, but alas it wasn't there. Chapter 5
is probably the most relevant part (feel free to read just the text, and
ignore or skim the mathematical equations):

[http://www-biba.inrialpes.fr/Jaynes/cc05e.pdf](http://www-
biba.inrialpes.fr/Jaynes/cc05e.pdf)

"...it might be thought (and for some it is an article of faith in democracy)
that open discussion of public issues would tend to bring about a general
consensus on them. On the contrary , we observe repeatedly that when some
controversial issue has been discussed vigorously for a few years, society
becomes polarized in to opposite extreme camps; it is almost impossible to
find anyone who retains a moderate view.

New information given simultaneously to different people may cause a
convergence of views; but it may equally well cause a divergence. This
divergence phenomenon is observed also in relatively well controlled
psychological experiments. Some have concluded that people reason in a
basically irrational way; prejudices seem to be strengthened by new
information which ought to have the opposite effect. Kahneman & Tversky (1972)
draw the opposite conclusion from such psychological tests, and consider them
an argument against Bayesian methods. But now, in view of the above ESP
example, we wonder whether probability theory might also account for this
divergence and indicate that people may be, after all, thinking in a
reasonably rational, Bayesian way (i.e., in a way consistent with their prior
information and prior beliefs)."

"...verbally, they have reasoned as follows:

A: "Mr. N is a fine fellow, doing a notable public service. I had thought the
drug to be safe from other evidence, but he would not knowingly misrepresent
the facts; therefore hearing his report leads me to change my mind and think
that the drug is unsafe after all. My belief in safety is lowered by 20.0 db,
so I will not buy any more."

B: "Mr. N is an erratic fellow, inclined to accept adverse evidence too
quickly. I was already convinced that the drug is unsafe; but even if it is
safe he might be carried away into saying otherwise. So hearing his claim does
strengthen my opinion, but only by 5.3 db. I would never under any
circumstances use the drug."

C: "Mr. N is an unscrupulous rascal, who does everything in his power to stir
up trouble by sensational publicity. The drug is probably safe, but he would
almost certainly claim it is unsafe whatever the facts. So hearing his claim
has practically no effect (only 0.005 db) on m y confidence that the drug is
safe. I will continue to buy it and use it."

The opinions of Mr. A and Mr. B converge in about the way we conjectured in
(5-20) because both are willing to trust Mr. N's veracity to some extent. But
Mr. A and Mr. C diverge because their prior probabilities of deception are
entirely different. So one cause of divergence is, not merely that prior
probabilities of deception are large, but that they are greatly different for
different people."

