There once was a young man called “dthat”
Whose name Frege made faces at.
But when Kaplan said “No,
Gottlob, say it ain’t so”,
His friends all agreed dthat was dthat.
Note: David Kaplan was my dissertation advisor. I owe him more than I can say. For his support and friendship and great good humor, I am eternally grateful. Kaplan is, of course, immortal, and will remain so for all time. But now I have extended his immortality with this limerick.