As a hockey referee, I would often find myself entertaining unsolicited advice from coaches.
“You are an idiot,” they would helpfully suggest. This tended to result in more penalties for the team in question, at which point the coach would, rethinking his strategy, attempt to deepen it (“You are a giant idiot”) reframe it (“Have you considered the possibility that you are an idiot?”) or broaden it (“You are an idiot and a moron”). I have to confess that none of these strategies was particularly effective in altering my decisions. Indeed, owing to my years of experience, I am prepared to categorically state that telling someone they are an idiot is a singularly ineffective way to influence human behaviour.
But at least the coaches were open and honest about it. It’s one thing to be called an idiot, but quite another to be treated like one. The latter tends to be even less effective in influencing behaviour, which is why I am surprised that environmentalists continually resort to it.
