Human folly's been famous since hist'ry began,
But to fathom the kind of mistake
That a frail human being will make
In dealing with matters of chance
From a sound psychological stance
You must study the writings of Amos and Dan.
"When Linda was younger, her sole career plan
Was an activist's life to pursue.
Now, which seems more likely to you:
Answer A: She's a clerk in a bank.
Answer B: She's a clerk in a bank
But an Occupy leader at night."
"B's more likely! That's gotta be right."
"Representative bias," said Amos and Dan.
"We've chosen at random a middle-aged man
From eight lawyers and two engineers
He's popular, handsome, and thrifty.
Which job has he worked at for years?"
"Could be either; it's just fifty-fifty."
"They're ignoring the base rate," said Amos and Dan.
Now, many psychologists claim that they can
Show that men without fail have good sense
And that human behavior is wise.
They ignore what's in front of their eyes.
But we scorn all this flimsy pretense,
And we stand by the science of Amos and Dan.
This is part of the collection Verses for the Information Age by Ernest Davis