Well I think that, ultimately, everything is potentially testable and verifiable or debunkable. We may currently lack the understanding or expertise, but we can predict that the testability will one day be possible. I pronounced my null hypothesis, which is the challenge in science to bring forth your evidence. If you propose something for which evidence is entirely lacking then you're not very interesting. If the thing you propose has been deliberately put beyond scientific enquiry, then you're a scoundrel. Supernatural deities fall into the second category along with flying spaghetti monsters and fairies at the bottom of the garden, and telepathy treads the perilous tightrope between the two. We can be kind and simply say that those who harbour any of these notions are suffering from delusions. The real world is already so marvellously complex and beautiful and intriguing in its magic. If that isn't good enough for you, then you must be missing out somehow.

By the way, Newton believed in alchemy.