At 8:27 AM -0400 9/19/00, Miguel Roig wrote:
>At 04:11 PM 9/17/00 -0500, you wrote:
>>The violation occurs in the fact that no one has been able to identify any
>>physical radiation of any known energy source during brain activity that
>>can be detected beyond the skull.
>
>So, because the mechanism for a phenomenon cannot yet be accounted for, we
>should toss out any evidence of the phenomenon?
Science is a process of choosing among alternatives.
In an ideal experiment, there might be only two:
1. The results are due to the independent variable.
2. The results are due to random variation.
In the real world we usually have more:
3. The results are due to errors in experimental control.
4. The results are an artifact of human frailty (wishful thinking,
outright fraud, etc).
5. The results are a false positive; negative results have not
been published (really a special case of #2).
When the purported mechanism lacks corroborating evidence from other
sources, we must consider the relative likelihood of the other alternatives.
It's not a question of *tossing out* evidence, but in accounting for it.
>>Further, psi signals (unlike anything
>>known to physics) do not seem to obey the inverse square law (they do not
>>degrade as a function of distance).
Again, the below presents a somewhat contrived case where a signal might be
intelligible (but with a measurable loss of both magnitude and
intelligibility) independent of distance, or at least over a wide range of
distances.
The inverse square law does apply; there are also other factors affecting
the signal.
Again, the onus is on those presenting the argument for psi to show that
these unlikely conditions do in fact hold.
Lacking evidence of any strong effect, experimental flaws and false
positives seem the most likely of the alternative accounts.
When (as in the Ganzfeld experiments) someone seals ping pong ball halves
over their eyes and procedes to walk around a room avoiding objects and
naming them, reading signs, etc (like Luke Skywalker learning to use a
light saber in Star Wars) we'll have a convincingly strong and reproducible
effect.
As I've argued before, small effects over large numbers of trials beg for
an alternative explanation in terms of experimental flaws.
>In a pretty good, but now somewhat dated book on parapsychology, Edge, Morris,
>Palmer, & Rush (1986) point out a nice argument against the incompatability of
>psi with the inverse-square law. These authors write: "Hoffman (1940) noted,
>the inverse-quare decline aplies ot the power of the carrier wave, but ESP
>scores would depend upon the _intelligibility_ of the information. Radio
>reception is a familiar analogy: speech remains fully understandable over a
>wide range of distances. Further, the inverse-square law rearely applies in a
>practical situation, because of reflection, refraction, scattering and other
>effects, including intentional beaming. Spacecraft have transmitted picture
>signals over nearly a billion miles with power of only a few watts becasue the
>energy was concentrated in a narrow beam to earth"
>
>The reference for the book is:
>
> Edge, H. L, Morris, R. L., Palmer, J., & Rush, J. H. (1986).
>Foundations of
>parapsychology: Exploring the boundaires of human capability. Boston, MA:
>Routledge.
>
>The reference for Hoffman is:
>
>Hoffman, B. (1940). ESP and the inverse-square law. Journal of
>Parapsychology, 4, 149-152.
>
>
>>You can find more detailed analyses at <http://www.csicop.org/si/>.
>
>In the absence of a more specific reference, I am sure one can find arguments
>against some of those detailed analyses in the various parapschological
>journals. See http://www.rhine.org/.
I'll let the physicists make the arguments about what is good physics.
* PAUL K. BRANDON [EMAIL PROTECTED] *
* Psychology Dept Minnesota State University, Mankato *
* 23 Armstrong Hall, Mankato, MN 56001 ph 507-389-6217 *
* http://www.mankato.msus.edu/dept/psych/welcome.html *
