in your own words, tell me the main idea of this paragraph: "Some people boast of having a sixth sense, where they profess to know or see things that others cannot. Fortunetellers, mind readers, and mystics are at the top of this list of those who lay claim to mysterious powers. In so doing, they instill widespread fascination in others, especially book publishers and television producers. The questionable field of parapsychology is founded on the expectation that at least some people actually harbor this talent. To me, the biggest mystery of them all is why so many fortune-telling psychics chose to work the phones on TV hotlines instead of becoming insanely wealthy trading futures contracts on Wall Street. Quite independent of this profound mystery, the persistent failures of controlled, double blind experiments to support the claims of parapsychology suggest that what’s going on is non-sense rather than sixth-sense."