How can we identify scammers in this site as believers?
I hope a believer wouldn't be trying to scam. But, if you're asking how to tell scammers apart from believers I can only say guard yourself against fraud no differently than you would in real life. The internet makes people more bolder, but your willingness to help and caution should be no different than how you would interact with people in real life.
I have seen worse in real life, not just the "virtual world".
The act and transmission of money for unknown reasons to unknown people with no known accounting or legal framework is a clue.
Yes Good question Francis but if scammers was so easy to detect they would not be a problem. If you close one loophole they soon find others.