"I know you," said Alice. "Are you to present me with a puzzle? Perhaps one of you tells the truth and the other lies?"

"Oh no," said Bingle-Dum.

"We both lie," added Googl-E.

"But there must be a clue," pouted Alice. "For how else am I to tell when to trust what you say?"

"That's the point!" laughed Bingle-Dum.

"We don't know when we're telling the truth either!" said Googl-E, finishing the other's sentence.