For those who simply refuse to believe that there is a spiritual realm.....that demons exist, that angels exist, etc.....simply because they can't see them (I know several people who have......and they're far saner than many here)will just sit back, guffaw, spout sarcasm, and call these people quacks, idiots, charlatans, or worse.
...and they're wrong.
I will not go into my own personal experiences here, and I DAMNED well guarantee I'm as sane as anyone. Suffice it to say that those who pooh-pooh the concept of life after death....and the existence of evil....are gambling with something they don't want to gamble with.