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Even people who are not "numbers people" may have a soft spot for one number in particular: 7. For various reasons, many of us find it fascinating, even magical.
Consider: Bestselling books feature it in their titles, (e.g., The Seven Habits of Highly Effective People), articles use it to intrigue readers (e.g., Seven Characteristics of Emotionally Strong People), and the mere sight of three sevens standing side-by-side can make us shriek with excitement—especially if we happen to be standing by a slot machine with a plastic bucket of quarters.
What is it about the number that causes such a visceral response? Why didn’t any slot-machine manufacturers make their jackpot sequence three ones in a row or even three fives? After all, one and five are perfectly good numbers. The fact is that, historically, the number 7 has played a significant role in society, culture, religion, and even psychology.
Here are 7 reasons we are so drawn to the number:
1. It has been significant since ancient times. It was prominent in many ancient cultures. Most famous of all were the seven wonders of the world which comprised a bucket list for every world traveler — the Great Pyramid of Giza, the Hanging Gardens of Babylon, the Temple of Artemis at Ephesus, the Statue of Zeus at Olympia, the Mausoleum at Halicarnassus, the Colossus of Rhodes, and the Lighthouse of Alexandria.
2. It has had significance in almost every major religion. In the Old Testament the world was created in six days and God rested on the seventh, creating the basis of the seven-day-week we use to this day. In the New Testament the number seven symbolizes the unity of the four corners of the Earth with the Holy Trinity. The number seven is also featured in the Book of Revelation (seven churches, seven angels, seven seals, seven trumpets, and seven stars). The Koran speaks of seven heavens and Muslim pilgrims walk around the Kaaba in Mecca (Islam’s most sacred site) seven times. In Hinduism there are seven higher worlds and seven underworlds, and in Buddhism the newborn Buddha rises and takes seven steps.
3. It is associated with luck and magical properties. Seven not only represents the jackpot on slot machines, but it s also the basis for many myths and folklore. For example, various parts of the world had beliefs about the seventh son of a seventh son, legends that endowed him with magical powers of both the good and evil variety (e.g., the child was believed to have healing powers according to Irish folklore).
4. It matches our memory capacity. In 1956, George Miller of Harvard University wrote what is today considered one of the classic papers in psychology in which he demonstrated that most people can retain roughly seven items of information in their short-term memory. That is why phone numbers in the U.S. and many other countries tend to have seven digits (area code not withstanding) — as it is the most digits most people are likely to recall (although cell phones have done away with the need to recall anyone's phone number, even our own).
5. It fits our attention spans. Because of our mental capacity favoring seven items, seven is also a good fit for our attentions spans, as long as the information is presented in seven groups. While bloggers and authors tend to take advantage of this fact, some seem to take more advantage the others. For example, the book: 7 Pages to Success: The Ultimate Short-Attention-Span Guide to Unlock Your Full Potential! is only 7 pages long, which is fine, but it costs $7 (!), which leads me to believe the only real potential being unlocked is that of the author’s bank account.
6. It is a prime number. Prime numbers are those that can only be divided by themselves and by the number 1, and have long been considered special to mathematicians and non-mathematicians alike. Seven is considered by some to be the most ‘prime’ number within the first 10 numbers as you cannot multiply it within the group, making it a kind of optimal-prime (not to be confused with Optimus Prime, who is a Transformer).
7. It is the most popular number. The mathematician Alex Bellos asked 44,000 people to name their favorite number and over 4,000 of them named the number 7, far more than any other number. Indeed, ask people to name a number from one to ten and many will name the number seven — as many magicians know.
It is this combination of cultural, historical, religious, numerical, and psychological factors that contribute to the allure of the number 7 and the sway it has over our decisions. For example, my book, Emotional First Aid: Healing Rejection, Guilt, Rejection, and Other Everyday Hurts, was initially supposed to have eight chapters (one for each psychological ‘wound’) but after consulting with my editor, I decided to reduce the number of chapters (and wounds) to seven (loss, rumination, loneliness, and low self-esteem, in addition to the three in the subtitle) as I believed focusing on seven psychological wounds would be easier for readers to absorb and to recall rather than eight. Was I correct? Check out the book and let me know.
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Copyright 2015 Guy Winch
