have faith/believe/trust your gut and all that jazz. No, think it through, take some insight into the situation, use your goddamned mind. I hate the idolisation of faith, I do not understand how faith by itself is somehow good. (Note I have no problem with the religious or anything, I just don't see why faith is good).
Could care less.
I mean, really? n't. That's all you need: n't.
It's just a theory.
'slap'
and of course: Because I said so.
Don't hear it too much anymore but if someone says that to me they can expect a laugh of derision and subsequently being ignored. No, justify yourself, unless we're in a situation where trust is important (eg little time) I will not trust you blindly and will fully expect you to explain why I should do something where there is little or no merit in me doing it.