The last day of March and so the last day (at least in legend) of the breeding season of the hare, when they all go a little crazy. To mark the occasion, here's a snippet from the tea party where Alice meets a mad Hatter, a Dormouse, and a March Hare, and has a lesson in semantics.
The Hatter opened his eyes very wide [and said] “Why is a raven like a writing-desk?”
“Come, we shall have some fun now!” thought Alice. “I'm glad they've begun asking riddles.—I believe I can guess that,” she added aloud.
“Do you mean that you think you can find out the answer to it?” said the March Hare.
“Exactly so,” said Alice.
“Then you should say what you mean,” the March Hare went on.
“I do,” Alice hastily replied; “at least—at least I mean what I say—that's the same thing, you know.”
“Not the same thing a bit!” said the Hatter. “You might just as well say that I see what I eat is the same thing as I eat what I see!”
“You might just as well say,” added the March Hare, “that I like what I get is the same thing as I get what I like!”
“You might just as well say,” added the Dormouse, who seemed to be talking in his sleep, “that I breathe when I sleep is the same thing as I sleep when I breathe!”
“It IS the same thing with you,” said the Hatter, and here the conversation dropped, and the party sat silent for a minute, while Alice thought over all she could remember about ravens and writing-desks, which wasn't much.