Hannibal arranged everything on the desk carefully, then sat and waited for everyone to arrive.

Once they were there, he nodded. "We discussed last week what makes something food, why some things are or aren't. This week, we have another question. Why do we eat?"

He waved at the food and drink. "There are the obvious answers; most people will say, 'we eat because we're hungry'. But it is rarely so clear-cut. Each section here is a pair of foods. You may eat or drink only one from each pair. Choose one - or neither - and explain to us why. Feel free to debate it with each other as well. Feel free to ask me or each other questions."

He leaned forward. "Remember, there are no wrong answers; it's the reasoning we're after."