Introduction to Logic


Use the arrow keys to navigate the board and collect hints. When you figure out whether or not one person likes another, click on the corresponding box at the bottom of the page - once to say yes, twice to say no, three times to cycle back again. Once you have chosen yes or no for all possibilities, press the Submit button. Press the Show Answers button if you are stuck. To start over, press the Reset button.

Dana likes Bess and Cody. Nobody likes herself.
Bess does not like Dana. Only one person likes Abby.
Bess likes everyone that Abby likes.
Cody likes everyone who likes her. Abby likes Cody or Dana.

Abby likes herself. Bess likes Abby. Cody likes Abby. Dana likes Abby.
Abby likes Bess. Bess likes herself. Cody likes Bess. Dana likes Bess.
Abby likes Cody. Bess likes Cody. Cody likes herself. Dana likes Cody.
Abby likes Dana. Bess likes Dana. Cody likes Dana. Dana likes herself.