I believe in the power of positive thinking, secularly speaking, and prayer, speaking from faith. I don't think it's foolproof, from either perspective, in an imperfect, sometimes random world. Acting as if it is, or retrospectively attributing it to that in some "told ya so" type way... I could see how that would be rather rude and irresponsible, morally speaking.
There's something to be said for confidence being a boon in certain situations, and negativity being a hinderance... However, these are only situations in which one's behavior and interactions are key to the process. Something like being hit by a car isn't one of those, unless as a result of said anxiety they had a weird compulsion to jaywalk.
The worst kind is blaming ill people for their illness because they aren't "positive enough". Yes, because if he/she were more chipper, his/her cells would not have spiraled out of normal metabolic processes and proliferated beyond control.
The only thing I can think of to make this true is someone thinking to themselves "gosh, I really don't want to make it through today..." and hurling themselves into an oncoming bus. They thought negatively and made it happen. But I really doubt someone thinking "I really hope a bus doesn't hit me" is going to help if they don't do something about it, just thinking idly really does little.
I think if you feel really negative and mad then all that negative energy causes bad things to happen. Like do you notice when things are already as bad as it can gt then all the sudden youwill stub your toe, then r out of toilet paper, and then your boyfriend calls and says he isnt comming home tonight, and then the computer is slow and boots you off. Yeah I know what I am talking about, my life story lol