Published in the Biblical Bulletin 8 (Spring 1979): 1-2 and in The Reporter (Lansdale, PA) 111, no. 146 (18 April 1981): 17.


Biorhythms: the New Astrology

Robert C. Newman


In the past two or three years, the “science” of biorhythms has been sweeping the country.  For 25Ę you can have your own biorhythm reading for any day of your life.  For $20 a computer will give you readings for a whole year.  For $10 you can buy a little hand calculator to figure out your own readings.


What is this “science” of biorhythms?  Early in the 20th century, two German doctors claimed to have discovered that human behavior is strongly influenced by three rhythms:  a physical cycle repeating every 23 days, an emotional cycle of 28 days, and an intellectual cycle of 33 days.  In each of these cycles, a person is supposed to be strong (physically, emotionally, or mentally) in the first half and weak in the second.  These cycles are all supposed to start off from zero when you are born and continue without variation to the day you die.  Thus calculation of your biorhythmic status at any time is relatively simple if your birthdate is known.


In addition to giving information about your “good days” and “bad days” for physical, emotional or mental activity, it is claimed that an “critical days” (when one or more cycles are switching from strong to weak or vice versa) you are especially prone to have accidents.  Much of the popularity of biorhythms is based upon claims that knowledge of this “science” has significantly cut accident rates in some industries.


In spite of such claims, however, there are several suspicious features of biorhythms which are immediately obvious.  Why should the cycles start at birth?  A baby is alive for months before he or she is born.  In addition, some babies are born prematurely, others come many days overdue.  What evidence is there that all people have the same length cycles?  There is hardly any human trait that is exactly the same for everyone.  And what evidence is there that the length of any of these cycles is unchangeable throughout life?  Very few of our personal characteristics remain the same as we age.  Yet if any of these cycles differs by even a few tenths of one percent from exactly 23 (28 or 33) days, then the usual calculation will be worthless for anyone more than twenty years or so old.  By then, the peaks of each cycle will actually come were you calculate valleys!  To make any really valid use of biorhythms, you would have to have a very thorough and expensive physical examination to find out (if indeed it is possible to find out) where you are in each cycle.  An elaborate checkup would be needed every year or so to make sure of the exact length of your cycles and to see whether or not their lengths are changing.


As a matter of fact, recent studies in this country indicate that biorhythms as popularly calculated are worthless for predicting performance.  Thus, Reggie Jackson, right fielder of the New York Yankees, hit three home runs in his last three at bats to win the 1977 World Series on a “low day” in his physical cycle!  A study of the batting performances of 70 major-league baseball players during the 1975 season showed no connection with their high days, low days, or critical days.  Similar research on 205 carefully investigated auto accidents in which a driver was clearly at fault likewise showed no link between accidents and critical days.  The same result was found for an analysis of 400 mining accidents.


Are there some lessons here for us?  Yes.  Don’t run off after every fad tht comes along.  “Test all things; hold fast to that which is good.”  Mankind, it seems, has a great thirst for security.  Sometimes this involves dabbling in occult forms of divination, such as astrology, Tarot cards, seances or ouija boards.  For others, there is an unbalanced emphasis on making money, winning friends, gaining power, or even just trying to stay healthy.  God wants us to concentrate on doing His will, and He in turn will provide us with the only real security there is.  Where else can one truly find that “all things work together for good,” that even when we fall, “underneath are the everlasting arms”?