Someone once quoted the same to the philosopher W. V. O. Quine. To which Quine is said to have replied, "Possibly, but my concern is that there not be more things in my philosophy than there are in heaven and earth." Quine, of course, is applying one of the oldest and most reliable tools of rational knowing, Ockham's Razor: Don't multiply explanations needlessly. If a paranormal phenomenon can be reasonably explained as some combination of coincidence, intuition, wishful thinking, the placebo effect, fraud, and so on, then let's dismiss it and get on to phenomena for which we can find reproducible evidence. This does not mean, of course, that what we presently understand in science is the be all and end all of knowing. There may be whole continents of knowledge yet to be discovered and explored.
Books like Mayer's- and there are thousands of them- argue, on the one hand, that paranormal phenomena by their very nature elude the methodologies of science, and then go on to amass what the authors purport to be scientific evidence- a curious disconnect to say the least. I would quote the philosopher Rebecca Goldstein: "So can there be good evidence for nonscientific propositions? No. Because the minute there is good evidence, it becomes science."
So it all comes down to evidence. Reproducible, non-anecdotal evidence that can be amassed by believers and skeptics alike. I choose to live within the paradigms of a way of knowing that has proven stunningly successful- scientific naturalism hedged with Ockham's Razor. Others, the great majority of humans, happily inhabit supernaturalist and paranormal paradigms for which reproducible evidence is in woefully short supply. "