Yeah, I really could have modeled this post much better than I did. I don't know why it came out so horrible. Perhaps I was really tired when I wrote it? Anyway, I will answer the questions and such now.
First of all: No, you woudn't have to trick their psyche in order to make something like that work. If you want it to happen that badly
(lets say the spell cast is a pestilence curse, to make the person sick) then if they cough or sneeze at all you will imediately thing
it worked. It sounds silly to say that, but our subconcious can literally alter the way we think. Our sanity isn't quite as safe as
we'd like to think, easily altered through tricks of the mind, drugs, and of course, life itself.
Secondly: I can agree with the whole "defining satan" thing. However, A lot of religions actually do consider anyone not with them, against them.
With the main religions here, such as christianity and catholocism, I find its pretty split. Not all of christians and catholics are like that
obviously, but I have encountered equal numbers of christians/catholics that have that mind set as opposed to those that don't. In those who
think that way's eyes, anyone not with them is against them. They have to have a reason why, and its almost always pinned on satanism.
Magic and religion are very odd indeed. I really shouldn't have gotten into religion with this piece of writing but the damage
is done.

I honestly don't know what happened the night of that note. I wasn't on drugs or anything, and I'm pretty sure I wasn't
angry at religion, so I can only think that I was really tired and didn't put as much thought into it as I should have.