“Ford Prefect suppressed a little giggle of evil satisfaction, realized that he had no reason to suppress it, and laughed out loud, a wicked laugh.”

“"Oh, goddamn! What the hell?!" [opens fire, then laughs] "Suppressing fire!"”

“He bursts out laughing. It's short, as if he regretted allowing me to make him laugh, but the satisfaction's already mine.”

“Laugh often, long and loud. Laugh until you gasp for breath.”

“You hear that boy laughing?—you think he’s all fun;
But the angels laugh, too, at the good he has done;
The children laugh loud as they troop to his call,
And the poor man that knows him laughs loudest of all.”

“Religion acts as a moral gardener, to weed out, or suppress, evil tendencies, which, like weeds: grow.”

“He had an idea that even when beaten he could steal a little victory by laughing at defeat.”

“Man, when he realizes that he is an object of comedy, does not laugh.”

“Arthur Dent: What happens if I press this button?
Ford Prefect: I wouldn't-
Arthur Dent: Oh.
Ford Prefect: What happened?
Arthur Dent: A sign lit up, saying 'Please do not press this button again.”

“One of the things Ford Prefect had always found hardest to understand about humans was their habit of continually stating and repeating the very very obvious.”