The Skeptics Society & Skeptic magazine

The Mars Effect &
True Disbelievers

by Geoffrey Dean

According to Alexander Panchin in Vol. 16, No. 1, if you take 535 people in any profession and count the frequency of any planet (out of 10) in any two sectors (out of 12) at their birth, and randomize everything a million times, the highest mean total is nonsignificantly different from the observed total for Mars in sectors 1 and 4 for 535 eminent sports champions. So the Mars effect is “a statistical anomaly and nothing more.”

Such an explanation has been touted by skeptics again and again (Panchin is decades away from being the first), but it cannot possibly apply. Why? Because right from the start it was known that planetary effects (not just Mars effects) replicate—a point stressed in three of the references Panchin cites. Replication requires profession, planet and sectors to be specified in advance, so counting any planet in any two sectors for any profession is not relevant, especially when you assume that planets move independently (they don’t), that expectancies in each sector are equal (they aren’t), and that demography doesn’t matter (it does).

Incidentally Gauquelin did not use 535 champions (the Comité Para did), and 535 does not appear anywhere in the reference that Panchin cites for it. Nor were eminent sports champions the start of it all (it was eminent doctors).

Michel Gauquelin (1928–1991) was a Sorbonne graduate in psychology and statistics, and was fully aware of everything Panchin implies he was ignorant of. So his first priority after observing planetary effects was to see if they replicated. And they did. Again and again. Not just in France but also in Holland, Belgium, Germany, Italy, and America for a total of nearly thirty thousand eminent births. This work was done in the 1950s through the 1980s.

In 1987 the statistician I.J.Good “tried to dwindle the Mars effect, partly by allowing for ‘special selection’ of planet and attributes, and managed to get the Bayes factor down to about 60, but faced with the Saturn, Jupiter, and Moon effects, this approach will clearly not undermine Gauquelin’s results” (Journal of the American Statistical Association 98, 697–698, 1987).

Nor did tests by skeptics. Two decisive tests are shown in my figure. The results support a Mars effect.

Underlying both tests were True Disbelievers behaving badly towards (for them) inconvenient results. The Comité Para claimed that errors existed despite their own clear evidence to the contrary, which for eight years they failed to disclose. CSICOP spent five years dodging and weaving and casting personal slurs. Dr Richard Kammann (a CSICOP Fellow and co-author of The Psychology of the Psychic) spent seven months sifting the published papers and unpublished background papers and letters. He concluded that the CSICOP skeptics “have persisted in offering to the public a set of demonstrably false statistical arguments against the Mars effect in spite of four years of continuous and steadily mounting criticism of their illogic. … When the whole record is examined over five years, there is almost no instance in which merit wins out over self-serving bias” (Zetetic Scholar 10, 50–65, 1982; see 66–73 for articles on the Comité Para test).

Today there are eight independent studies and nearly thirty of Gauquelin’s replication studies. Meta-analysis confirms that planetary effect sizes are tiny (mean r = 0.044) but significant, see my chapter 13 in Brian Farha’s Paranormal Claims: A Critical Analysis (2007).

The problem of course is one of explaining how planets (not all of them, just some of them) could have an effect on people (just eminent people, not the 99.994% on Gauquelin’s figures who are not eminent), albeit with tiny effect sizes that could not be explained by artifacts of astronomy, demography, bias, data selection, or fraud (all favourite ploys of desperate skeptics). But there’s more.

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Why no link with physical variables such as size and distance? Why no link with the Sun? Why is eminence important? Why is the effect larger for less-precise birth times? (This is like saying the more we tune our radio the worse the reception—it is definitely not what we expect.) And so on. It is these puzzles, not just planetary effects, that are the real challenge of Gauquelin’s work.

In fact the misreporting of birth data by a mere 3% of parents to suit pop astrological ideas current at the time seems enough to explain all the puzzles, see my article in Skeptical Inquirer for May/June 2002 available online. Most of the relevant births are from the 19th and early 20th centuries when planetary positions were publicly available and misreporting was easy. Its success at explaining all the puzzles (and the total failure of other artifacts) should dispel any doubts about its relevance.

Furthermore, misreporting (when possible) is almost universal. Eminent Americans and Congressmen misreport their birth date to make it coincide with a significant day, thus allowing “image enhancement through unit associations between oneself and positively evaluated stimuli” (Social Psychology Quarterly 51(4), 365–370, 1988), at a level notably more than for Gauquelin’s eminent professionals. Modern Asians control things at even higher levels to achieve birth years deemed auspicious by Chinese astrology (Population and Development Review 17, 663–686, 1991).

But misreporting will not explain planetary effects unless the effects disappear when births are reported by doctors instead of by parents, as was increasingly true in Europe after the second world war. As yet nobody knows if they do or not. But it could be argued that Gauquelin’s failure to observe a consistent Mars effect for sports champions born after 1950 has already put this point to the test. All that heat under the True Disbelievers’ collar seems to have been premature.

Sadly the existence of misreporting in birth data did not emerge until after Gauquelin’s death. He was ever the perfect scientist, always philosophical, confiding with a grin that he might or might not be right, and never sure he would live to see the puzzles solved. Today it seems clear that he was right and the True Disbelievers were wrong.

ABOUT THE AUTHOR: Geoffrey Dean is a technical editor in Perth, Western Australia, and a Fellow of the Committee for Skeptical Inquiry. He and his associates have been contributing critiques of astrology to Skeptical Inquirer since 1985.