Encyclopedia of Leadership

6.1

THE BS DETECTOR KIT:

RECOGNIZING ERRORS OF LOGIC

Inspired by John Paulos and Carl Sagan.

Leaders need tools for detecting erroneous logic. Not only is this tool interesting reading, but

by occasionally reviewing the fallacies pointed out here, you will sharpen your instincts for

detecting logical errors in your own thinking and in that of others.

LOGICAL FALLACIES

170 SECTION 6 TOOLS FORCRITICALTHINKING ANDINNOVATION

Attacking the person,

not the problem—ad

hominem

Vague terms

Defining the problem

as a solution

An either-or false

dichotomy

Confusing association

and correlation with

causation

Sequence means cause

The statistic of small

numbers—over-

generalizing

Misunderstanding the

nature of statistics

Incorrect conclusions—

non sequitur(It does

not follow.)

Pleading

Blindly trusting

authority

Selective observation

Logic error What it is Example

Attacking the arguer rather than the

argument or the facts

Using vague terms rather than stating the

real, concrete issue

Presenting a solution to an as-yet undefined

problem

Presenting only two alternatives when a range

is available

Causation cannot be assumed just because

something routinely happens after a certain

event.

Just because two thing happened in sequence,

that doesn’t necessarily mean one is causing

the other.

Making general inferences from a very small

sample

Making incorrect statistical inferences

Drawing incorrect conclusions from data

Appealing to some authority or law to

support an argument

An argument that amounts to little more

than “Trust me”

Using only selected pieces of evidence to

support your argument

“You’re a typical engineer; you’ll never understand

human needs.”

“We have a communications problem” rather

than, “You and I haven’t spoken since the

incident.”

“We need to send all our Systems Analysts to an

interpersonal skills workshop.”

“Either you take the transfer or you’ll have no

career here.”

“We have a lot more absences on Mondays

because people get paid on Fridays.”

“Chris seemed upset after getting negative

feedback yesterday. Now he called in sick today.”

“I talked to a couple of customers and nobody

likes the new design.”

“Over half of the statistics you hear are wrong.”

“We have more lost-time accidents this month.

Our new safety program isn’t working.”

“It’s human nature for people to ...(e.g., be

selfish, want to help).”

“If you work hard, the company will take care of

you.”

“Twice this week, Terry has been whispering on

the phone. Someone must be getting fired.”