Originally Posted by Dr. Keith
Well, it's not really just religion. You mostly hear the word faith in conjunction with religion, only because the same thing is called by another name in virtually any other domain.
Namely, faith is what is called a "delusion" in any other domain than the exemptions made for religion or culture. No, really, beliefs held against evidence are by definition delusions. Again, in any other domain.
Quite literally if I believed that there's a peeping tom watching me in the shower, even when provably there's nobody there -- and for bonus points, my bathroom doesn't even have a window -- it would qualify as a delusion. But if I believe that Jesus watches me in the shower, you know, to make sure I don't wash my dick too fast or anything, then that's ok. Replace Jesus with Santa, and it's a delusion again. Make it a ghost, and yep, it's a delusion again.
"Delusion" having strong negative connotations is also the reason why you don't hear much about it outside of religion. People don't go around advertising their delusions, because they learn pretty quickly that it makes a negative impression. Which is why you don't hear many advertise that they have faith in ghosts or in Elvis still living, for example. Or not without first making sure that the other person is at least not opposed to such beliefs. You know, for example start with "I saw a documentary on TV" and back out if the other person goes some version of, "oh ffs, not that nonsense again."