Ravens, Writing Desks, and this thing called Vanity

“Why is a raven like a writing-desk? Have you guessed the riddle yet?” the Hatter said, turning to Alice again.
 “No, I give up,” Alice replied: “What’s the answer?”
 “I haven’t the slightest idea,” said the Hatter.   Neither do I yet this riddle from Lewis Carroll’s Alice in Wonderland remains firmly planted in my…