Take heart, religious believers: recent research isn't evidence of God, heaven, soul, or the afterlife, but it could point to something similarly mysterious.
There's a lot of controversy surrounding Daryl Bem's claim that precognition is real. But his paper is going to be published in the respected Journal of Personality and Social Psychology. An article in New Scientist says:
Extraordinary claims don't come much more extraordinary than this: events that haven't yet happened can influence our behaviour.
Parapsychologists have made outlandish claims about precognition – knowledge of unpredictable future events – for years. But the fringe phenomenon is about to get a mainstream airing: a paper providing evidence for its existence has been accepted for publication by the leading social psychology journal.
What's more, sceptical psychologists who have pored over a preprint of the paper say they can't find any significant flaws. "My personal view is that this is ridiculous and can't be true," says Joachim Krueger of Brown University in Providence, Rhode Island, who has blogged about the work on the Psychology Today website. "Going after the methodology and the experimental design is the first line of attack. But frankly, I didn't see anything. Everything seemed to be in good order."
However, good order is in the eye of the scientific beholder.
Some Dutch researchers argue that Bem's work reflects weaknesses in how findings are analyzed statistically. Their Bayesian approach, which I don't claim to understand, showed no evidence of precognition.
Regardless, the effect wasn't huge, just a few percent above the 50-50 that would have been expected by chance. It's cool, though, that Bem's first experiment used erotic images.
In his first experiment, Bem explored the effects of erotic stimuli on perceiving the future. After being shown an image, one hundred Cornell students — 50 male and 50 female — were each shown pictures of two curtained screens on computer monitors, one covering a blank wall, the other covering the image. Many but not all of the pictures behind the curtains were erotic images, such as those of “couples engaged in nonviolent but explicit consensual sexual acts,” according to Bem’s paper. Each participant was to click on the curtain which he or she thought had the picture behind it.
Bem hypothesized that 50 percent of those who were shown erotic stimuli would identify the correct curtain, and that those shown erotic pictures would have a higher “hit rate” — the number of times that the correct curtain was identified — than participants that were shown non-erotic pictures.
In the 100 sessions, the hit rate for those shown erotic stimuli was 53.1 percent, while the 49.8 percent hit rate of those shown non-erotic pictures did not deviate from chance. This shows that on average, given that the erotic image shown to the participant made a considerable impression, that participant’s ability to foresee the future is statistically higher than chance, according to Bem.
“The remarkable finding [we made] is that their physiological responses are observed to occur about 2-3 seconds prior to the appearance of the picture, even before the computer has decided whether to present a non-arousing or an arousing picture,” Bem said.
Well, I'm open to the possibility that something outside of our current understanding of the laws of nature and causation is going on here. But Bem admits that he doesn't have any firm hypotheses about what that might be, a fact that disturbs the above-mentioned Joachim Kreuger.
The whole point of psi experiments is to demonstrate the existence of something that is inexplicable by ordinary lights. If it were explicable, it would not longer be anomalous; it would not be psi.
That's the paradox. Psi research seeks to establish the existence of weird phenomena while at the same time refusing to offer a positive theory of why and how these phenomena come into being. This must be so because once you have a positive (i.e., intelligible) theory about the process underlying the phenomenon, the mystique is gone.
If you want to dig deeper into Bem's research, a preprint of his journal paper is the place to go. I browsed through "Feeling the Future: Experimental Evidence for Anomalous Retroactive Influences on Cognition and Affect," skipping the numbers and focusing on conclusions.
If psi exists, then it is not unreasonable to suppose that it might have been acquired through evolution by conferring survival and reproductive advantage on the species (for a discussion, see Broughton, 1991, pp. 347–352).
For example, the ability to anticipate and thereby to avoid danger confers an obvious evolutionary advantage that would be greatly enhanced by the ability to anticipate danger precognitively. It was this reasoning that motivated Experiment 2 on the precognitive avoidance of negative stimuli.
Similarly, the possibility of an evolved precognitive ability to anticipate sexual opportunities motivated Experiment 1 on the precognitive detection of erotic stimuli. The presentiment experiments were probably inspired by similar reasoning.
And after attempting (more accurately, in my opinion,straining) to invoke quantum mechanics as an explanation of precognition, Bem says:
Unfortunately, even if quantum-based theories eventually mature from metaphor to genuine models of psi, they are still unlikely to provide intuitively satisfying mechanisms for psi because quantum theory fails to provide intuitively satisfying mechanisms for physical reality itself.
Physicists have learned to live with that conundrum but most non-physicists are simply unaware of it; they presume that they don’t understand quantum physics only because they lack the necessary technical and mathematical expertise. They need to be reassured.
Richard Feynman (1994), one of the most distinguished physicists of the twentieth century and winner of the Nobel Prize for his work on quantum electrodynamics, put it this way:
"The difficulty really is psychological and exists in the perpetual torment that results from your saying to yourself, ‘But how can it be like that?’ which is a reflection of uncontrolled but utterly vain desire to see it in terms of something familiar....Do not keep saying to yourself...‘But how can it be like that?’ because you will get...into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that [emphasis added]. (p. 123)"
Comments on Kreuger's Psychology Today skeptical blog post about the research also are interesting (if sometimes technical) reading. This one hits on a point that was on my mind:
Psychology is such a joke. A demonstration of future events influencing present events would be one of the most important (if not *the* most important) findings in the history of mankind. Yet this demonstration doesn't end up in Science or Nature, but is published in the Journal of Personality and Social Psychology? And some wonder why psychology is still considered pseudoscience....