Most of us can enjoy a good argument — not a fight but an argument — a lively exchange of contradictory ideas. Arguing is an ancient and noble activity, and one of the very best ways to stimulate the sluggish brain cells, and perhaps to learn something at the same time. In teaching we still use the Socratic method of asking questions and challenging the answers, although Socrates, like me, asked more questions than he answered. At my old school the teachers set up debates, in which we had to argue one side of a question, then switch to the other side and argue for that. It taught us to see both sides, even if we only believed one. It wouldn’t do any harm for all schools to encourage old-fashioned debates like this. It’s fun, and it may even open some closed minds. But schools rarely take such a risk now because, in any debate, somebody is going to have to speak for the unspeakable side, and the unspeakable side might win.