"You can’t tell them," droned the psychologist slowly, "because that would hurt and you mustn’t hurt. But if you don’t tell them, you hurt, so you must tell them. And if you do, you will hurt and you mustn’t, so you can’t tell them; but if you don’t, you hurt, so you must; but if you do, you hurt, so you mustn’t; but if you don’t, you hurt, so you must; but if you do, you—"