The trouble is we tend to to over-simplify these sorts of situations when discussing them, but it's different when we encounter them in real life isn't it? To be honest, long ago when my two year-olds insisted on walking on the road rather than the pavement I didn't spend too much time arguing with them but grabbed them and made them safe. Of course we then explain to them about the danger of road traffic, but two-year-olds are not particularly strong on logical persuasion and pretty well advanced in defying parents, so it's a gradual process over many months to get the message over, and a lot of physical intervention in the meantime.
So what's the difference between immediately physically intervening with a child compared with an adult? I'm assuming that the situation is urgent and that there is a very real risk of someone being badly hurt. It seems to me that it's to do with the mental and emotional competence of the person concerned, and whether they are in possession of the right knowledge and skills to react OK themselves. If someone becomes mentally disturbed, suicidal and runs amuck with a machete then I guess no-one would object if they are physically restrained before trying to talk them down.
On the other hand, there are situations where it's far more tricky to work out what to do. As I've said before in the forum, I delayed stopping my father driving until his dementia was fairly well advanced, and I agonised over it for months. He wasn't going to decide to stop on his own, and his ability to live independently was only possible because he could still get around in his car. In the end I got the UK licencing authority to insist on a medical assessment, which he failed. It was the right thing to do, but I felt so very bad about doing it. This was a much greyer situation to deal with than a threat of suicide. It really spotlights how difficult these situations can be because I had to take his freedom of choice away from him without his consent - but if I hadn't and he'd gone on driving until he hurt himself or someone else badly, then this would have been very much on my conscience and I would have been at fault for not intervening before then.
These situations are all different, they are frequently messy and we are often left either with doubts about what to do, or a false confidence that we do know what to do. Some of them are slow burns, like with my dad where the situation just crept up on us slowly over a year or so, and there was no threshold event that said a line had been crossed. Other's like my toddlers need instant action with no time to think. In all cases, though, there are two ways to get the situation wrong, and it's vital in pondering the principles of intervention that both types of error are fully considered. One is to forcibly intervene when it's the wrong thing to do, crosses someone's boundaries and was none of our business to start with. The other is to not intervene and watch in horror as a disaster unfolds that we could have prevented. What we really want is one of the other two possibilities of course - to intervene and avert a bad situation, or to stand back and let the person concerned work through their problems OK.
To be honest, when I've been in these situations I've realised that the average human being hasn't the wisdom of Solomon and that all we can do is form a judgement as best we can. Even professionals with years of experience of dealing with folks in trouble can get it wrong. I guess what seems more important to me is not to try too hard to be a black belt virtuoso in the ethics of these situations, but at all times to act with as much wisdom as we have - and especially to act in love and good faith. We may well get it wrong in particular situations, but that is part of life and we learn by getting things wrong and doing better next time as a result.
