My dear friend Allison walked up to me and asked me what her birthday was.

"You forgot your own birthday?" I questioned her, with a puzzled look on my face.

"No," she said, "I mean I want you to remember it. You don't remember anything!"

"At least give me a hint," I pleaded.

Eventually she gave in. "First week of November."

Now, she and I are masters at logic. I myself knew it near instantly. Do you know what it is?