A few months ago I noted an interesting paper by respected psychologist Daryl Bem which appeared to provide some support for the idea that humans have some precognitive ability (‘seeing the future’). A couple of weeks ago this news ‘went big‘, with major news agencies around the world covering it. Given the attention foisted upon Bem’s experiments, and the controversial nature of his conclusions, it’s little wonder that scientist and skeptics have focused on this paper (still unpublished, by the way!) to try and find flaws in the methodology and analysis.
One of the first to dive in with a “big announcement” about Bem’s experiment was psychologist Richard Wiseman – little wonder, given that Wiseman loves himself some publicity, and Bem’s conclusions run counter to his public pronouncements/skepticism about psi. To be fair, Wiseman did point out a flaw in Bem’s method: allowing non-blind scorers to fix spelling errors in participant responses, which could have led to subjective bias in the scoring of tests. Bem has since responded to Wiseman’s criticism, labeling it a “legitimate concern”, but also noting that taking it into consideration makes “little difference to the results”.
More heavyweight responses came in the ‘negative replications’ mentioned by Jonah Lehrer in his Wired article about the precognition experiments (Galak & Nelson [2010], and Hadlaczky [2006]). However, Bem has pointed out that “Galak and Nelson went ahead with their trial without having full information about how his own experiments were conducted. They also had their experimental subjects take the test over the Internet rather than in person.” A commenter at Dean Radin’s blog (‘Sandy’) also showed it was possible to cheat on the test to increase the likelihood of getting a null result. In short, the kind of ‘replication’ that skeptics would reject if the results were positive. Given that Hadlaczky’s paper is from 2006, I am unsure whether it is a genuine replication of Bem’s most recent experiments. Similarly, a recent paper by Thomas Rabeyron and Caroline Watt had (largely) negative results, but again wasn’t an exact replication. And another paper dismisses Bem’s results because he should have used ‘conservative’ statistical tests rather than ‘liberal’ ones, a criticism which Dean Radin has responded to at his blog, and Ben Goertzel has discussed at length as well. Radin has also noted that he has just reviewed a soon-to-be-published positive replication of one of Bem’s experiments.
Feeling like your brain is now scrambled? Can’t say I blame you – it just goes to show how difficult it is to reach a consensus view on these controversial topics. So where do we go from here in judging Bem’s precognition experiments? I think it’s clear that we have to wait for *actual* replications of his methods, because everything so far seems to have not been precisely the same. But I can at least categorically say that you shouldn’t base your judgement on anything written by non-scientists at the James Randi Educational Foundation, and you shouldn’t even read the brain vomit that Robert Todd Carroll comes up with at the Skeptic’s Dictionary.
Oh, and in case you were wondering – the irony isn’t lost on me as to pondering the future outcomes of a precognition experiment…
