That’s exactly why the Randi challenge is a good test.
If psychic powers exist as a real skill, then surely someone – sooner or later – would have decided to demonstrate their skill for a million dollars.
If psychic powers don’t exist, no claimed psychic who is making any money as such would take the risk, because they (on some level) know they cannot pass.
The latter is exactly what we have seen. A lot of nobodies have tried, with complete lack of success, but the big names haven’t. Why? They know they will fail. If psychic abilities really did exist, why not take the opportunity to become the first proven psychic? I sure would jump at the opportunity to win a million dollars from using a skill I have. I don’t think any of them would turn down a free million dollars, so what’s the problem?
Of course, some argue that the test is unpassable, and what have you. Okay, then, why not set up your own test and prove that you can demonstrate psychic abilities? Why not prove Randi wrong? Again, nobody has managed to do this. Why not, if psychic abilities exist?
The fact of the matter is that high-profile psychics will never submit to testing whatever the criteria. You’re exactly right, they have too much to lose – and, as they know, also nothing to gain because they cannot pass any such test.
Any effect that is not detectable cannot have a demonstrable effect on the events of the real world. If the information can’t be detected, it can’t be used, because we don’t know it. You can’t claim on the one hand that psychics solve crimes but on the other that proof is undetectable; the two statements contradict each other.
If psychics can make meaningful predictions, then those predictions can be studied and confirmed or refuted. If they can’t be confirmed or refuted because there’s no way to determine a good prediction (based on changing skill level, various events, the alignment of Jupiter and Mars, or whatever) then psychic predictions are meaningless and can’t signify anything. That’s just simple logic.