I've been having another look at Chris Carter's excellent book Parapsychology and the Skeptics, which I reviewed here. It's out in a new edition with the title Science and Psychic Phenomena: The Fall of the House of Skeptics. It looks good (although the original was good too).
In a new postscript, Carter says he came to write the book after stumbling across a website devoted to debunking the belief in an afterlife.
Having read several serious books on the subject, I was shocked by the crudity of the author's arguments and by his utter ignorance of the vast amount of research that has been done on the topic over the past 12 years. I sent him an e-mail message, trying to get him to reconsider his dogmatic position, and, to my surprise, he responded with counterarguments. For the next few weeks, we engaged in a debate via e-mail, and I learned much about the so-called "skeptical" mind-set. I realized that it was based upon a certain set of metaphysical assumptions that were not treated as assumptions but as incontrovertible facts; and that it was also based upon an ignorance of certain facts that cast strong doubts on the validity of those assumptions.
I also realized that nothing I could possibly say would ever change his "skeptical" opinion. He had made up his mind, and that was that.
When I first read Carter's book I was impressed with the detail and clarity he brings to the descriptions of ganzfeld and other controversies. This time I've been paying more attention to his treatment of the philosophical challenge raised by psi, which is just as important. It's silly for sceptics to say there's no evidence for psychic functioning, but fair enough that they should have misgivings about how it fits in with established science.
A classic way to deal with the problem is to state that for psi to be true, science would have to be completely turned on its head, or "unravel all the way back to Galileo". I like this idea, like knitting coming undone (I think it comes from Steven Weinberg, or maybe James Alcock.) But intuitively I always thought it was crock. Psi has nothing to say about Newton's laws of motion, or the laws of thermodynamics, optics, chemical interactions, etc. It seems instead to have implications for the underlying basis of all matter, the realm of quantum mechanics, which at present is very imperfectly understood.
The Copenhagen interpretation, which seems to be the most commonly accepted, is that the act of measurement causes the collapse of the wave function into individual particles. The result depends on the observation; it is not a property of the electron itself. But in this interaction, if I understand it correctly, a mechanical device will do the trick just the same as a human observer. This never made any sense to me; it looks like an evasion, of the kind that physicists, not being philosophers, would easily content themselves with.
Carter focuses instead on mathematician John Von Neumann's idea that it's consciousness itself that collapses quantum possibilities into facts. This interpretation is a strictly minority view among physicists (although it was promoted by Eugene Wigner and others). How could consciousness, a product of matter, exert a causal influence on matter?
But it's remarkable, as Carter quotes physicist Nick Herbert saying, that the claim should come 'not from an otherworldly mystic in private meditation but from one of the world's most practical mathematicians deducing the logical consequences of a highly successful and purely materialistic model of the world - the theoretical basis for the billion-dollar computer industry'.
Carter goes on to describe a time-displaced PK experiment by physicist Helmut Schmidt, in which signals from a binary random event generator were recorded simultaneously on two cassette tapes, without anyone listening to them. One tape was given to a subject to listen to, with instructions to produce more 0s or 1s (usually in the form of clicks on the left or right of stereo headphones). When the results were analysed the influence of PK was observed. However the results also matched the other tape, which had been untouched.
One interpretation is that PK reached back in time to when the random events were originally generated. But a more interesting possibility, consistent with the Von Neumann interpretation, and put forward by Schmidt and his co-experimenters, is that events are not physically real until there has been an observation.
From this viewpoint, the PK effort would not have to reach into the past because nature had not yet decided on the outcome before the PK subject, the first observer, saw the result. Then, the PK effort should no longer succeed if we have some other observer look at the pre-recorded data previous to the PK subject's attempt. [An] experiment to study this situation ... has, indeed, reported a blocking of the PK effect by a previous observation.
The Von Neumann theory inevitably tends to invite quasi-theological speculation. What happened before there were conscious observers? If consciousness was needed to create humans - as conscious observers - then God or supernatural beings enter the equation. Carter quotes quantum theorist Euan Squires:
It is remarkable that such ideas should arise from a study of the behavior of the most elementary of systems. That such systems point to a world beyond themselves is a fact that will be loved by all who believe that there are truths of which we know little, that there are mysteries seen only by mystics, and that there are phenomena inexplicable within our normal view of what is possible. There is no harm in this - physics indeed points to the unknown. The emphasis, however, must be on the unknown, on the mystery, on the truths dimly glimpsed, on things inexpressible except in the language of poetry, or religion, or metaphor.
Sceptics could legitimately look for faults in experiments like Schmidt's to save themselves the bother of thinking about any of this. They can also complain - as they do - that quantum mechanics has been misappropriated and misunderstood by the spirituality community. But they would not convince me that there is not a mystery here, or that physicists are the people who really understand what's going on.