This answer to the question "How can you convince a crazy person that they are crazy? " is amazing

Nathaniel White
Nathaniel White, Creative at M&C Saatchi
There is a simple psychological technique for exactly this purpose.
It is incredibly effective at inducing compliance if they are proving very resistant.
First, you need to record how many cars are parked in your street each day. And when you get home each night, wrap everything electrical in tin foil.
Then copy out relevant passages from the Old Testament. And eat them in alphabetical order. But if the word ‘no’ appears in a passage - then you have to check the kitchen for clues.
If there is any salt you didn’t spill lying around - you will know they have got the message.
But watch out - it’s all too easy for them to paint you as the crazy one.
That’s the kind of crazy mind-games they play.
…Me, I’m a buddhist. We think everyone's crazy. All sentient beings are deranged.
So the idea is: you don’t convince someone they are crazy. You see they are suffering and think of ways to help.
I also work in advertising. And trust me - one thing I have learned is this: people hate advertising. No one wants to be sold to. Or told what to think. Least of all about how they think.
If you have powerful arguments - you are not going to be welcomed. You are a conquering army seizing control.
Do not persuade. Do not tell them something they don’t want to hear.
Tell them something they believe, or want to hear.
That way - they will want your help. Because you really are helping them.
You’ll be offering directions, not grabbing the steering wheel.
It seems to me that - especially in America today - diagnosis of psychological problems is being used as a power play.
‘You are sick. You need help’ is not an offer of help - it is an attack.
Psychological interventions should not trick.
They should treat.
You might think that I’m being unfair; blaming you for trying to help.
And assuming I know better; and insulting you by calling you the crazy one.
Well, exactly.