Good post. My reservations on the theory that psychic powers are inherent but latent, are that if psychic powers evolved over millions of years as a natural part of our being, it would be a huge advantage and therefore in theory it should have become dominant rather than latent, and with all the people there are ( billions now ) it should be as unambiguous as any other of our five primary senses. Still, I can't help but feel on an intuitional level that there is some truth in it. So while I'm sure that some subjects could be manipulated into believing they are having a psychic experience when they're not, that in itself doesn't necessarily rule out the possibility of the real thing, and the real thing may include an imparted and/or inherent but genuine experience. So we have three possibilities for a causal factor, all of which may play a part. The trick it would seem, is how to determine which is correct in any given example?
My reservations on the theory that psychic powers are inherent but latent, are that if psychic powers evolved over millions of years as a natural part of our being, it would be a huge advantage and therefore in theory it should have become dominant rather than latent, and with all the people there are ( billions now ) it should be as unambiguous as any other of our five primary senses.
Asimov made this argument and I believe explored it in some of his books. But I'm not so sure it's that straightforward. After all, aren't there genes that remain in the population at a very small but constant rate - they never get stamped out or spread? Some of these may even be useful in certain times and places or be leveraged by their owner for individual success but don't confer universal success or prove to be unattractive to mates. Extremely physically attractive men and women may provoke distrust and jealousy for example and so have a hard time finding mates.
Have a look at
Mephisto in Onyx by Harlan Ellison for another possibility. The main character had nothing but contempt for most people around him and could only find solace with someone whose mind
he could not read.
People have evolved both the ability to deceive and to detect deception - even persons with extreme guile are usually caught out. Serial killers may charm some victims and cause the hair to stand up on others. Someone always sees through the demagogue, even with true charisma. Nietzsche talks about his grandmother who was able to
see through people and how people hated her for it. I bet we all know someone who makes us uncomfortable because we feel like they know what we and everyone else is thinking. I'm not claiming a paranormal explanation here to make the point, it's enough that someone be naturally gifted in body language and other skills, but still that person gets "detected" by others.
So, would Psi
necessarily have an open field to develop and spread or would it be stamped back? Maybe.
Another possibility is that gene(s) for Psi are linked more directly to mental illness or autism or other traits that confer a disadvantage. Or that genes for Psi are elicited (epigenetics) only in certain conditions (this might tie in with the Trickster theory of eruption of Psi events in de-stabilized social conditions).
Of course, these are just possible counter-arguments to the above - not positive arguments that psychic powers are inherent.
Another possibility is to look at the idea of developing these abilities. A mundane example is strength training. The average man can increase his strength significantly with modern weight training techniques. There have always been traditional ways of strengthening the body but it's safe to say these generally don't compare to modern weight training. And not just training, compare the average
steroid and growth-hormone enhanced bodybuilder to the Greek ideal and he (she) could be considered some type of mutant if not an alien being or God. Some athletes who would never be competitive with training alone may possess a superior genetic response to chemical enhancement and be a "champion" by today's standards, whereas someone of naturally superior physical potential may simply not respond to the drugs available . . .
Specifically grip training is relevant here. With modern technology (spring loaded grippers of anodized aluminum) we have discovered that there is a remarkable potential for training human grip strength. Even weightlifters who do not specifically train the grip come nowhere near maximizing this potential and might exhibit less strength than an average man who focuses on this kind of training.
Similarly, we have developed abilities unheard of in previous generations (computer programming, driving, flying an airplane) because there was no call for them, the technology not extant or through biofeedback we can alter what was assumed to be unconscious aspects of physiology (of course there was some traditional training in these areas too) but biofeedback now might be used to treat illnesses or to control prosthetic limbs and probably results in a faster training response compared to traditional methods.
A small inherent Psi ability (if it could be brought under consistent control) perhaps amplified by chemical or other enhancement might be all that would be needed to control practically any device.
And if this Psi effect occurred despite time, distance and shielding . . .
Finally, if Psi is not like a primary sense but is a complex cognitive skill (or requires a complex cognitive skill to utilize) then it would be appropriate to compare measurement of Psi in the laboratory with measurement of other complex cognitive skills in the laboratory.