In the rough-hewn parlor of a creaky, 19th-century farmhouse in Brentwood, 13 people are sitting in a pair of concentric circles.
Six "reds" — or conservatives — are in the middle.
Around them on the outside, sit seven "blues" — or liberals.
"Don't look at them. Don't talk to them. We'll just talk among ourselves," commands Bill Doherty, a family therapist who teaches at the University of Minnesota. "Those of you who are in the blue group, your job is to listen and learn something here."