Sanderson M. Smith

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Did you know that fear of 13 has an official name? Yes, it really does!

It is called TRISKAIDEKAPHOBIA ... and it affects many people in our society.

It has been estimated by various sources that U.S. businesses lose millions of dollars because of canceled appointments, absenteeism, etc. on Friday, the 13th.

You can use MATH POWER and prove that with our present calendar, the GREGORIAN CALENDAR, every year must have at least one Friday, the 13th. Recent Friday the 13th's ...

Friday, October 13, 2000.

Friday, April 13, 2001 and Friday, July 13, 2001.

Friday, September 13, 2002 and Friday, December 13, 2002.

Can you find at least one that will occur in 2003? (MATH POWER says there must be at least one.)

Many great mathematicians, including the amazing Pythagoreans (around 550 B.C.) were number mystics. Even today, many religions attach extremely special significance to certain numbers.

What is absolutely fascinating is that there is no satisfactory explanation for the genesis of TRISKAIDEKAPHOBIA (fear of the number 13). But, here are some interesting observations:

* Industrialist Henry Ford wouldn't do business on Friday, the 13th.

* Multimillionaire Paul Getty once stated "I wouldn't care to be one of thirteen at a table."

* President Franklin Delano Roosevelt would not dine in a group of 13 people.

* Many hotel guests refuse to stay in Room 13, so rooms are frequently numbered 12, 12A, and 14.

* Some speculate that a fear of the number 13 is the reason we recognize only 12 constellations in the Zodiac, omitting a thirteenth... Ophiuchus ( the Serpent Holder) that, by its location, could be included.

* The ancient Hebrews thought 13 was unlucky because the thirteenth letter of the Hebrew alphabet is the letter M, which is the first letter in the word "mavet," meaning death.

* Some believe that 13 is unlucky because it follows 12, which in ancient Babylonia, China, and Rome was considered to be a lucky number associated with completion and perfection.

* Years ago, London bakers were subject to harsh penalties if they were caught selling bread in what was called short weight. The bakers would add an extra loaf to each dozen to be sure the sale met the minimum weight requirement. They avoided the word thirteen and the process of adding an extra loaf became known as the "baker's dozen."

Some like to trace the origins of fear of the number 13 to the Biblical version of the Last Supper.

(Mark 14: 17-21)

"And it was in the evening that he came with the twelve. As as they were at the table eating, Jesus said 'Truly, I say to you, one of you will betray me, one who is eating with me.' They began to be sorrowful, and to say to him one after another 'Is it I?' He said to them, "It is one of the twelve, one who is dipping in the same dish with me. For the Son of man goes as it is written of him, but woe to that man by whom the Son of man is betrayed! It would have been better for that man if he had not been born.' "

The inference is clearly that one in the group of 13 is doomed.

I repeat, however, that there is no meaningful evidence to suggest that this Biblical passage is the source of TRISKAIDEKAPHOBIA. The origin of fear of the number 13 is a mystery.


"I know numbers are beautiful. If they aren't beautiful, nothing is."

-PAUL ERDOS (1988)


"If a man's wit be wandering, let him study the Mathematics."

-FRANCIS BACON Essays (1625)


"It is hard to convince a high-school student that he/she will encounter a lot of real problems more challenging than those of Algebra and Geometry."



"How can it be that mathematics, being after all a product of human thought independent of experience, is so admirable adapted to the objects of reality?"



"The advancement and perfection of mathematics are intimately connected with the prosperity of the state."


[Interesting historical note: NAPOLEON was an outstanding mathematician. Three other people not generally associated with mathematics who were outstanding mathematicians: President JAMES A. GARFIELD, the great poet HENRY WADSWORTH LONGFELLOW, and LEWIS CARROLL (Alice in Wonderland )].


SOCRATES: "What Plato is about to say is false."

PLATO: "What Socrates has just said is true."





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