THE WORLD OF DR. BAYESA WORK IN PROBABILITY · EST. 2026
EPISODE 001 · THE POSTERIOR

The Free Drink

An introduction to changing your mind. The bartender offers Dr. Bayes another whiskey. New information changes everything.

PriorsUpdating beliefsWhiskey
THE COMICTap any panel to open it at full size
Episode 001 of the Dr. Bayes comic, “The Free Drink”: The bartender offers Dr. Bayes another whiskey. New information changes everything. The full dialogue is in the transcript below.
01 / 03Panel 1 of 3 from Episode 001, “The Free Drink”
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A NOTE FOR CURIOUS MINDS

Behind the joke.

A prior is your starting belief. New evidence can change it. In the comic, an ordinary whiskey offer becomes considerably more appealing when the bartender mentions the price. The scientific lesson is a little more demanding: weigh new evidence according to how informative it really is.

SPEECH BUBBLES, IN WORDS

The transcript.

For readers who prefer dialogue without zooming in.

Read the dialogue ↘

Bartender: Another whiskey?

Dr. Bayes: My prior says no.

Bartender: It's on the house.

Dr. Bayes: I've updated my beliefs.