This strip was originally published in the newspapers on May 27, 1990.
Calvin and Hobbes are playing Calvinball. Calvin stole Hobbes' flag. Hobbes hit him with the Calvin ball. He has to sing the "I'm very sorry" song. Calvin protests he was in the "no song" zone. Hobbes corrects him, as he had touched the "opposite pole", so now the "no song zone" is a "song zone". Calvin complains that Hobbes didn't declare it. Hobbes says he declared it oppositely by not declaring it. Calvin starts singing, and Hobbes joins in. When they're finished, Calvin says he gets free passage to wicket five. Hobbes tells him they did that last time. Calvin makes up a new rule to jump until someone finds the bonus box. As they jump away, Calvin says the only permanent rule in Calvinball is that you can't play it the same way twice. Hobbes says the score is "Q to 12".
This strip was also published in the following books:
Scientific Progress Goes 'Boink' on page 113
The Indispensable Calvin and Hobbes on page 241
The Calvin and Hobbes Tenth Anniversary Book on page 129
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