Lucky and Unlucky Numbers and Days: Friday the 13th to Four

Lucky and unlucky numbers and days are among the most widespread superstitions in the world: in Britain and North America people avoid thirteen and fear Friday the thirteenth, in China, Japan and Korea the number four is shunned because it sounds like the word for death, while seven, eight and nine are widely considered fortunate. Some of these beliefs rest on ancient calendars of good and bad days; others, including the fear of Friday the thirteenth, are surprisingly modern.

Lucky and Unlucky Days in the Ancient World§

The oldest surviving calendars of lucky and unlucky days come from Egypt. The so-called Cairo Calendar (Papyrus Cairo 86637), a New Kingdom document, classifies every day of the year as good, bad or mixed, often explaining the rating by events in the lives of the gods, and advises what to avoid on bad days, such as travelling or leaving the house at night.

The Greek poet Hesiod closes his Works and Days (around 700 BC) with a section on the days of the month: some are good for sowing, marrying or shearing sheep, while the fifth days are harsh, because on a fifth day the Furies attended the birth of the oath-god Horkos. In Rome, days after the Kalends, Nones and Ides were regarded as dies atri, black days, and the anniversary of the defeat at the river Allia (traditionally 18 July 390 BC) was a day of ill omen on which no public business was done. Ovid's Fasti is a rich source for Roman beliefs about the calendar, including the ill luck of marriages in May.

Egyptian Days and the Medieval Calendar§

Medieval Europe inherited a list of "Egyptian days" (dies Aegyptiaci), usually two in each month, twenty-four in all, on which it was dangerous to let blood, begin a journey or start a new task. They appear in many calendars and medical manuscripts, sometimes marked with a symbol. Their link to Egypt was believed, not demonstrated; they probably descend from late antique Roman tables of bad days. Churchmen from Augustine onwards condemned the observance of days as superstitious, yet the lists continued to be copied.

Within the Christian year, Holy Innocents' Day or Childermas (28 December), commemorating Herod's massacre of children, was widely held unlucky for beginning anything, and in some places the weekday on which it fell remained unlucky through the following year. Friday, the day of the Crucifixion, had a mixed reputation: it was a day of fasting and penance, and English sources from Chaucer onwards treat it as ill-starred. In the Nun's Priest's Tale the narrator laments that "on a Friday fil al this meschaunce". Sailors' reluctance to sail on a Friday is one late expression of this belief, discussed with other occupational lore in Superstitions of Sailors, Actors and Gamblers.

Thirteen and Friday the 13th§

The fear of thirteen people at table is recorded in England from the late seventeenth century, usually with the belief that one of them will die within the year. It was explained by reference to the Last Supper, at which Jesus and the twelve apostles made thirteen and Judas was the first to die. A Norse myth in which the mischievous Loki arrives as the thirteenth guest at a feast and brings about the death of Baldr is often cited as an older origin, but the number is not emphasised in the medieval sources and the connection is a modern interpretation.

The fear of thirteen in general, given the name triskaidekaphobia (a coinage usually credited to the American psychiatrist Isador Coriat in 1911), grew in the nineteenth century. In 1881 a group of New Yorkers formed the Thirteen Club to mock it, dining thirteen to a table on the thirteenth of the month. Friday the thirteenth as a specifically unlucky date is hard to find before the late nineteenth century. Its popularity owed much to Thomas W. Lawson's novel Friday, the Thirteenth (1907), about a stockbroker who exploits the superstition to cause a market panic, and to newspapers that seized on the date. Nathaniel Lachenmeyer's history 13 traces this development in detail.

Popular explanations attribute the date to the arrest of the Knights Templar by Philip IV of France on Friday 13 October 1307. The arrests did happen on that day, but no source connects them with an unlucky date before the twentieth century, and the link was popularised by modern fiction, as explained in Templar Legends. The superstition is not universal: in Spanish- and Greek-speaking countries Tuesday the thirteenth is the unlucky day (Constantinople fell on a Tuesday in 1453), and in Italy it is Friday the seventeenth, because the Roman numeral XVII can be rearranged as VIXI, "I have lived", that is, "I am dead".

Many buildings omit a thirteenth floor and many airlines a thirteenth row. Studies of whether the date is actually more dangerous have produced mixed and often tongue-in-cheek results, such as a short 1993 paper in the British Medical Journal on traffic accidents.

Tetraphobia: Four and Death in East Asia§

In Chinese, the word for four (sì) sounds very like the word for death (sǐ), differing only in tone; in Japanese, one reading of four, shi, is identical to the word for death, and in Korean sa likewise means both. The resulting avoidance of four, tetraphobia, is widespread in China, Taiwan, Hong Kong, Japan, Korea and Vietnam. Buildings omit fourth floors, and sometimes the fourteenth and twenty-fourth; Korean lifts often label the fourth floor "F"; hospitals avoid room numbers with four; gifts in sets of four are avoided; and telephone numbers and car registrations containing four are cheaper. In Japan nine is also avoided in some contexts, because one reading, ku, sounds like the word for suffering.

A much-debated 2001 study in the British Medical Journal reported a peak in cardiac deaths among Chinese and Japanese Americans on the fourth of the month and suggested stress as a cause; other researchers questioned the finding. Wider Asian beliefs about luck are covered in Asian Superstitions, and Chinese ideas of auspicious arrangement in Feng Shui.

Lucky Seven, Lucky Eight and Other Favoured Numbers§

Seven has long been a special number in Western culture: seven planets visible to the naked eye, seven days of the week, the seven days of creation and many sevens in the Bible, from the seven seals of Revelation to the seventh son of a seventh son credited in British and Irish folklore with healing powers. Its symbolism is discussed in Number Symbolism and on the number seven page. The modern phrase "lucky seven" probably owes as much to dice and card games as to sacred tradition.

Three is proverbially lucky ("third time lucky") and also unlucky, as in the belief that deaths come in threes or that lighting three cigarettes from one match is dangerous, a superstition often attributed to the Boer War or the First World War, though its origin is uncertain.

In Chinese culture eight (bā) is the luckiest number because it resembles fā, to prosper, especially in Cantonese, where the words are baat and faat. The opening ceremony of the Beijing Olympics began at eight minutes past eight in the evening on 8 August 2008, and numbers full of eights fetch high prices at auction. Nine (jiǔ) sounds like the word for long-lasting and was associated with the emperor. The number eight page covers Western numerological meanings.

At the other extreme, 666, the "number of the beast" in Revelation 13:18, gave rise to the modern term hexakosioihexekontahexaphobia. When Ronald and Nancy Reagan retired to a house numbered 666 in Los Angeles, the address was changed to 668.

Weekdays, Months and the Leap Year§

Folk rhymes assign character to the days of birth and luck to the days of washing, wedding and cutting nails; the best known, such as "Monday's child is fair of face", are treated in Superstitions of Birth, Marriage and Death. New Moon and New Year beliefs, such as turning money in the pocket at the sight of the new moon, are recorded in Britain from the eighteenth and nineteenth centuries.

The leap year illustrates how invented history attaches itself to a custom. The tradition that a woman may propose marriage on 29 February is often said to derive from a Scottish law of 1288 issued by Queen Margaret, fining any man who refused. No such law exists in the records, and Margaret, the "Maid of Norway", was a small child who never reached Scotland. An alternative legend involving Saint Bridget and Saint Patrick is equally late. The custom itself is recorded from about the eighteenth and nineteenth centuries, and its "ancient" charter was invented to explain it. For number lore more generally, see Numerology.

Frequently asked questions§

Why is Friday the 13th considered unlucky?§

It combines two older beliefs: that Friday is ill-omened, linked to the Crucifixion, and that thirteen is unlucky, linked to the thirteen at the Last Supper. The combination is not clearly documented before the late nineteenth century and was popularised in the early twentieth.

Did Friday the 13th come from the Knights Templar?§

No. The Templars were arrested on Friday 13 October 1307, but there is no evidence that anyone connected that event with bad luck before the twentieth century. The link was spread by modern novels and websites.

Why is the number four unlucky in China and Japan?§

Because the word for four sounds like the word for death in Chinese, Japanese and Korean. Buildings, hospitals and shops often avoid the number for that reason.

Why is eight a lucky number?§

In Chinese, eight sounds like the word for prosperity, especially in Cantonese. It is therefore prized in phone numbers, addresses, prices and dates, such as the 8 August 2008 opening of the Beijing Olympics.

Sources and further reading§

• 13: The Story of the World's Most Notorious Superstition — Nathaniel Lachenmeyer, 2004
• The Mystery of Numbers — Annemarie Schimmel, 1993
• Works and Days — Hesiod, c. 700 BCE
• Fasti — Ovid, c. 8 CE
• A Dictionary of Superstitions — Iona Opie and Moira Tatem, 1989
• The Penguin Guide to the Superstitions of Britain and Ireland — Steve Roud, 2003
• Numerology: Or What Pythagoras Wrought — Underwood Dudley, 1997
• The Stations of the Sun: A History of the Ritual Year in Britain — Ronald Hutton, 1996