"Honesty" isn't his only schtick--he also wants us to believe we are going around all the time making irrational decisions. Here's one putative "cognitive bias":
"Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in pro-choice rallies.
Which is more probable?
Linda is a bank teller, or,
Linda is a bank teller and is a feminist."
Fred says it's more probable that Linda is a teller who is a feminist. Barney says, no, it's more likely that she's a bank teller.
Who is right? Well, they both are--depending upon the meaning they give to the "or" given in the choices:
Linda is a bank teller, or,
Linda is a bank teller and is a feminist."
Barney interpreted "or" the way it is usually glossed in logic textbooks, as the "inclusive or". Under this interpretation, Barney is right, because the set of tellers is LARGER than the set of feminist tellers. So it has to be more likely that she is a teller.
Fred, however, interpreted "or" as the exclusive or. That's the "or" your mother means, when she says "I'll buy you either the squirt gun or the comic book." You don't say "oh goodie! I'll take them both!!" No, mom is just going to buy you one or the other.
Under that interpretation, the question means "Is it more likely that Linda is a bank teller who is NOT a feminist, or that she is a bank teller who IS a feminist?" So Fred is right under that interpretation. As is everybody who gives this answer on psychological tests, because most of the time in English, "or" means "exclusive or."
--//--
As far as I can tell, EVERY SINGLE example used to prove we have cognitive biases use this same trick:
Step #1: Find an ambiguous word or phrase ("or" in the above example),
Step #2; write the question so that test subjects will tend to interpret it one way,
Step #3: and then conclude they are irrational by adopting the other interpretation when evaluating the truth value of their answer.
Step #4: get tenure and lucrative corporate consulting gigs
"Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in pro-choice rallies.
Which is more probable? Linda is a bank teller, or, Linda is a bank teller and is a feminist."
Fred says it's more probable that Linda is a teller who is a feminist. Barney says, no, it's more likely that she's a bank teller.
Who is right? Well, they both are--depending upon the meaning they give to the "or" given in the choices:
Linda is a bank teller, or, Linda is a bank teller and is a feminist."
Barney interpreted "or" the way it is usually glossed in logic textbooks, as the "inclusive or". Under this interpretation, Barney is right, because the set of tellers is LARGER than the set of feminist tellers. So it has to be more likely that she is a teller.
Fred, however, interpreted "or" as the exclusive or. That's the "or" your mother means, when she says "I'll buy you either the squirt gun or the comic book." You don't say "oh goodie! I'll take them both!!" No, mom is just going to buy you one or the other.
Under that interpretation, the question means "Is it more likely that Linda is a bank teller who is NOT a feminist, or that she is a bank teller who IS a feminist?" So Fred is right under that interpretation. As is everybody who gives this answer on psychological tests, because most of the time in English, "or" means "exclusive or."
--//--
As far as I can tell, EVERY SINGLE example used to prove we have cognitive biases use this same trick:
Step #1: Find an ambiguous word or phrase ("or" in the above example),
Step #2; write the question so that test subjects will tend to interpret it one way,
Step #3: and then conclude they are irrational by adopting the other interpretation when evaluating the truth value of their answer.
Step #4: get tenure and lucrative corporate consulting gigs