Can contact bring two camps together? A depolarization simulator

A thousand simulated people in two camps, mostly connected to their own side. Each round, everyone talks to one contact and shifts toward views that are close enough to accept, and, if you turn on backfire, away from views far enough to reject. Pick an intervention and watch where the society goes.

Simulation, not a forecast. These are simulated people following a stated rule from the opinion-dynamics literature (Deffuant et al. 2000; Jager & Amblard 2005). How far real people accept or reject views has not been measured well enough to pin the two thresholds down, so the point is to see which conclusions hold across settings.

Controls

Far right = no backfire. Lower = people push away from more views.

Try these

Opinions over time

started in camp Astarted in camp Btime runs left to right, 400 rounds; opinion 0 at the bottom, 1 at the top

round0
gap between camps–
at the extremes–
near the centre–

Gap starts near 0.6. 0 means the camps merged; 1 means they sit at opposite extremes.

What the full sweep found

Each intervention at its largest dose, over 25 settings of tolerance (ε 0.2 to 0.4) and backfire (none, τ 0.9 to 0.6), 10 simulated societies each (from experiments/results.txt):

Intervention (dose)Merged the campsDrove more people to the extremes
Ladder of committed voices (20% of people)24 of 250
Broadcast a moderate view (heard 20% of rounds)190
Committed moderates at the centre (20%)191
One-off nudge to the centre (40%)140
Raise everyone's tolerance (+0.2)80
Bridge: rewire 50% of ties across camps210

"Merged" = at least 9 of 10 societies end with a gap under 0.1. "Drove more to the extremes" = the extreme share rose by more than 0.1 over no intervention. At τ = 0.6 the society splits to the extremes on its own, so no lever can make it worse there.