No. 84: Nov-Dec 1992
A great chasm separates the "hard" sciences from parapsychology. In fact, most scientists do not recognize para-psychology as a legitimate science. A recent spate of letters in Physics Today reveals both the depth of the chasm and why it is there. The major letter writers are P.W. Anderson and R.G. Jahn, who work only a few hundred meters apart at Princeton but are light years apart on the matter of parapsychology.
The letter writing commenced after Anderson wrote a column in the December 1990 issue of Physics Today entitled "On the Nature of Physical Law." Here he recommended the categorical dismissal of all anomalous observations that might tear apart the fabric of science. Although Anderson did not name Jahn specifically, it was obvious to Jahn that his work was the primary target. Jahn's response was a long letter summarizing the stupendous quantity of data he and his colleagues have amassed on psi effects.
"We have in hand several prodigious data bases, acquired over 12 years of continuous, intensive experimentation, that clearly establish the existence, scale and primary correlates of certain anomalous influences of human consciousness on a variety of physical systems and processes. In our Microelectronic Random Binary Generators experiment, 95 selected human operators attempted to shift the output distribution means to either higher or lower values than the chance mean, in accordance with their prerecorded intentions. In 3 850 000 experimental sequences of 200 binary samples, the overall results were that means in high intensity runs exceeded means in low intensity runs by 4.38 sigma. (The probability of chance occurrence of this outcome is less than 6 x 10-6 .)
Jahn also reviewed the results of other types of psi experiments which also produced positive results.
Replying to Jahn, Anderson admitted that he indeed had Jahn in mind when he wrote his original article.
"What my piece actually said was within my competence as a theorist, which is to make logical connections, and the logical point I made is that physics as it is practiced, and specifically precise mensuration, is not compatible with Jahn's claims; one must choose one or the other, not both, as he also emphasizes. If the 'observer effect' as he calls it -- or 'magic' as one might equally well characterize it -- is correct, precise measurement is not possible. His ideas are as incompatible with the intellectual basis of physics as 'creation science' is with that of cosmology and biology. It is for this reason that I feel measurements such as Jahn does must be tested with more rigor and more suspicion than their proponents, for some reason, are ever prepared to undergo."
In other words, if psi exists, one cannot measure anything exactly, because the experimenter's mind can skew the results.
(Jahn, Robert G., and Anderson, Philip W.; "A Question of Mind over Measurement," Physics Today, 45:13, October 1992.)