# seven

seven
7th
presentation
Roman VII
dual 111
Octal 7th
Duodecimal 7th
Morse code - - · · ·
Arabic ٧
Chinese
Mathematical properties
sign positive
parity odd
Factorization ${\ displaystyle 7}$
Divider 1, 7
Handwritten seven with and without a slash
Coat of arms of the Siebenhirten district of Vienna
The Nebra Sky Disc : 7 golden points are interpreted as a reference to the Pleiades .

The seven (7) is the natural number between six and eight . It is odd and a prime number .

## Numeral

In Germany, the number 7 is handwritten in three strokes according to the numerical spelling of the Latin original script : a horizontal line, from the right end of which a diagonal line is drawn down to the left. This is then provided with a horizontal line in the middle . This notation corresponds to the Austrian school script (identical information in the versions from 1969 and 1995) and the Swiss Schnürlischrift . It also takes place in Latin America . In the English-speaking culture and in areas influenced by it, a 7 is drawn without a dash. This notation can be misinterpreted as 1 in continental Europe and Latin America .

## Mathematical properties

The 7 is the lowest generator number in the set of natural numbers . The associated cyclic number is "142857". You can use this property to the result of the division of natural numbers by 7 without calculator to calculate quickly.

 1 : 7 = 0,142857142857… 2 : 7 = 0,285714285714… 3 : 7 = 0,428571428571… … 

A rule for divisibility by 7 leads to a simple algorithm to test the complete divisibility of a natural number by 7:

1. Remove the last digit and
2. double it and
3. subtract it from the remaining digits.
4. If the difference is negative, the minus sign is left out.
5. If the result has more than one digit, repeat steps 1 to 4.
6. If the result is 7 or 0, then the number is divisible by 7 - and not otherwise.

The example shows that 1547 is completely divisible by 7:

 154 - 2 7 = 140 14 - 2 · 0 = 14 1 - 2 4 = −7

The decimal number for the common fraction "one seventh" can be determined as follows:

  0.14 +0.0028 +0.000056 +0.00000112 +0.0000000224 +0.000000000448 +0.00000000000896 +0.0000000000001792 +0.000000000000003584 +0.00000000000000007168 +0.0000000000000000014336 +0.000000000000000000028672 +0.00000000000000000000057344 +0.0000000000000000000000114688 +0.000000000000000000000000229376 und so weiter ≈ 0.142857142857142857142857 ${\displaystyle =\sum _{n=1}^{\infty }{\frac {7\cdot 2^{n}}{100^{n}}}=\sum _{n=1}^{\infty }7\cdot 50^{-n}}$ 

## symbolism

The seven is the sum of three and four, of mind and soul on the one hand and body on the other, i.e. the human. In the traditional Christian number symbolism of the Middle Ages , the three stands for the soul and all spiritual things created in the image of the triune God. The four is the number of elements and is symbolic of the material things that, according to ancient belief, all arise from the combination of the four elements. In buildings, the heptagon was often used for graves and funerary chapels for eternal rest .

The number 7 is often viewed as a lucky number, but in many countries in East Asia (e.g. China or Thailand ) 7 is an unlucky number.

In addition to its number, the seven has a special position: the seven dwarfs behind the seven mountains in the fairy tale of Snow White , the seven wonders of the world , the seven days in a week and the creation of the world in seven days in the creation myth of the Hebrew Bible are only a relatively few of the many Terms in which the seven is mentioned. In a library, the seven appears much more frequently in book titles than the neighboring numbers 6 and 8. The same applies in lexicons to terms that begin with numbers.

Experiments in behavioral research show the preference for seven: the most common answer to the question about your favorite number or when asked about any number between one and nine is the number seven. Because the color “ blue ” is so often cited as a favorite color , this phenomenon is called the Blue Seven phenomenon .

When determining a whole random number from two to twelve as the sum of two dice , for example in some board games such as backgammon , the seven appears most frequently in the long term, because it can be combined with the six different combinations 1/6, 6/1, 2 / 5, 5/2, 3/4 and 4/3 can be displayed. It appears statistically six times as often as the two and the twelve (two only with the combination 1/1 and the twelve only with the combination 6/6), each three times as often as the three and the eleven, each twice as often as the four and the ten, each one and a half times as often as the five and the nine and each 1.2 times as often as the six and the eight.

## Attempts to explain the special position

The depth psychology provides an explanation for the special position . According to Josef Paneth , seven is the first prime number in the psychological sense, the number of taboos . It plays such an important role in the Bible because no people like that of the Old Testament are so restricted by taboos.

However, some authors assume that the seven did not get its peculiarity from the popular consciousness. Rather, the astronomical peculiarities and their perception were further cultivated by the Babylonians . A special position developed from the seven visible “ wandering stars ” that diffused into other cultures, peoples and religions. With reference to the relevant literature, an attempt is made here to show the development of the special position of the seven and their transmission through cultures, peoples and times. The “magnetism of the symbol seven, which continued to have an effect until the very last time” is also attempted to prove by statements such as that Austria would not have been accepted into the Rhine Union if there had not been a seventh in the league.

According to this diffusion theory, the occurrence of the special position of the seven in small ethnic groups in North and Central America remains unclear . The Nahua tradition allows the seven Nahua tribes to emerge in seven caves.

Another widespread attempt to explain the special position of the seven in many cultures is the presence of the seven openings of the human organs of perception in the human skull: two ears, two nostrils, two eyes and a mouth. The popular conception of the seven senses (sight, hearing, smell, taste, touch, orientation and balance) corresponds to this. The biological factors also include the number of teeth (7 per half of the dentition, above and below, if the wisdom teeth have not yet been created).

Another explanation could be the meaning of the seven in human perception and comes from the field of cognitive psychology and is called Miller's number . More than three hundred years ago, John Locke discovered the so-called "seven phenomena" when he was examining the perception of an adult. He found that test subjects who see a large number of objects for a brief moment have a hit rate of almost one hundred percent with up to seven objects. If there are more than seven items, the quota drops suddenly . We are z. B. is able to repeat up to seven digits a short time later after only one brief viewing , but very rarely more.

### The divine happening in the universe and its mathematical "proof"

Some authors assume that the special position of the seven is based on the observation of astronomical peculiarities. Seven is the number of apparently mobile celestial bodies that are visible to the naked eye at an early stage: the sun and moon , plus the planets Mercury , Venus , Mars , Jupiter and Saturn . In early societies, celestial events were understood as divine, these moving stars were equated with the gods. The naming of the seven days of the week still indicates this in many languages ​​(such as: Sunday (sun), Monday (moon), English Saturday (Saturn), French Lundi (moon), Mardi (Mars), Mercredi (Mercury) or Latin Dies Iovis (day of Jupiter)).

The Babylonians saw in these "signs of the overall order of the cosmos" their movements as "expressions of divine beings". From these seven " wandering stars " they developed the idea of ​​seven celestial spheres and then assigned seven rivers, seven colors, seven tones, and seven metals to the seven planets . Von Andrian pointed out that in all of the cultures, peoples and groups he studied, the seven “planets” or the seven “planetary spheres” always appear as the dwelling places of the gods or demons .

With Nicolaus Copernicus and the transition from the geocentric to the heliocentric worldview , the celestial movements over the seven "planets" were modified. The earth became a planet like the others, the moon became their satellite and the sun the center of the system. There were six real planets, the seventh planet Uranus wasn't discovered until 1781. In 1846 the eighth and later over 1000 planetoids were added with Neptune . However, the special position of the “seven” is based on the older and “naive” knowledge of people (with the naked eye exactly seven “wandering stars” are visible).

The moon phases are mentioned as an astronomical reason for the special position of the seven . Each lunar cycle is divided into four approximately seven-day weeks. In the oriental regions the moon was the supreme god and its periodic increase and decrease had to be "noticed by primitive man who observed nature far more than we".

Other special astronomical observations related to the number seven have always been made with the naked eye. Along the ecliptic there are seven bright astronomical objects with an apparent magnitude of at least 1.5 magnitudes, which can be regularly covered by the moon and observed in conjunction with all planets. Furthermore, the well-known asterisms Big Dipper , Orion and the Seven Stars each have seven main stars.

In ancient times, numbers were not only used in calculations, they had a symbolic meaning. The connection of the holy number with processes in space and in the world was clearly proven for the ancients: 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. Adding the first seven numbers gives 28, the number of days in a lunar cycle. For the ancients, the above addition was even the “mathematical proof” for the special position and importance of the seven in world events. The seven also has a special position in Babylonian mathematics , in the sexagesimal system of the Mesopotamians with the base number 60. The early astronomers could only assume the solar year to be 360 ​​instead of 365.25 days. In this 60 system, special attention is paid not to the seven, but to the trunk fraction one seventh (1/7). A seventh is the only stem fraction among those with a denominator between 1 and 10 that cannot be represented as a finite sexagesimal fraction .

### The special position of the seven in the Babylonian culture

The seven did not always have the most important and central role, the respective attribution of the seven as a lucky or unlucky number changed. In all the great mythologies of the Babylonian and following the Greek and Roman cultures, the number seven is found as a "special" number. It has a special position in its number symbolism. However, in most of Africa and America , in Australia and even in some European peoples, e.g. B. with the Albanians no “mystical” role. Ferdinand von Andrian therefore assumed a ›diffusion‹ of the mystical seven from the “oldest seat of culture in Mesopotamia ” through the many migrations and trade relations in the various world directions, which also spread oriental, magical-mystical cultural assets. He describes that an immediate takeover of the mystical seven occurs only sporadically in many European areas. An immediate takeover by the Eranians was practically impossible due to the lack of a meeting . B. in many Slavic areas only when the position of the seven was badly oppressed by the nine .

According to Joseph Paneth , the Babylonians took over the special position of the number seven in the 4th millennium BC from the Sumerians who lived in southern Mesopotamia. The existence of seven evil demons , the ebettu , who were created by the god An , who embodied the “infinity of heaven” for the Sumerians, could be an indication of this. In the astrology of the Babylonians, the Šebettu were identified with the seven brightly shining stars of the Pleiades : Their symbols are seven points.

Among the Semites , after Andrian, the Babylonians were the most ardent worshipers of the holy seven. Their mystical conception of the seven penetrated the popular consciousness of the Babylonians and Assyrians . According to Silver, under the Sumerian King Lugulannemundu around 2500 BC a temple with seven portals and doors was built for the goddess Nintu in Adab , for the inauguration of which 49 oxen and sheep, i.e. 7 times 7, were sacrificed. However, this information comes from a book about lucky numbers.

Analogous to the seven sacred "planets" in which the Babylonians saw the expression of divine utterances, they formed seven parts of the world, seven rivers, seven winds, seven metals and seven colors. Further examples of the seven in the Babylonian culture are the seven heavens , the seven cosmic towers with seven steps, the seven locks of Gilgamesh , the seven branches of the tree of life , the seven main stars on the great heavenly chariot, the seven names of Mars, the seven atonement rites , the serpent with seven heads or seven tongues, the seven gates of the underworld in the descent of Ištar into hell . Also, the Babylonian flood rises for seven days and falls for seven days. 1700 BC In the time of King Hammurabi in a Babylonian calendar, the 7th, 14th, 21st, 28th and 19 (30 + 19 = 49) of a month are said to have been viewed as unlucky days on which the king allowed certain things failed to make sacrifices. A hundred years earlier, under King Sargon, the five-day week is said to have been replaced by the seven-day one.

Seven also plays an important role with the Persians, it is the favorite number of the Eran hero sagas. Herodotus describes an Arabic oath in which seven stones are smeared with blood.

### The seven in ancient Athens and Rome

Seven against Thebes

In ancient Europe the seven had a special position, especially in the cult of Apollo , the number was consecrated to God. The Pythagoreans believed that numbers were endowed with mysterious powers and believed that the personified numbers rule world events. The “ten number” enjoyed almost divine veneration, but the number seven was still considered the number of rhythms of life. The seven is the sum of the square (4) and triangle (3). Philolaos , a pupil of Pythagoras , wrote in the 5th century BC A hymn to the number seven.

Examples of number seven in Greek mythology are the seven wonders of the world , the seven heroes of Thebes (" Seven against Thebes "), the seven seas , the heptathlon . The seven wonders of the world changed more frequently in history, their number always remained the same. This also applies to the "seven" wise men.

The division of life into seventies probably comes from Solon , one of the " seven wise men ". These seven years are still significant in anthroposophy today .

A broken mirror means seven years of bad luck, followed by seven years of happiness.

In Roman mythology , the seven stands for the god Neptune . The Ancient Rome was on seven hills built: Palatine , Capitoline , Quirinal , Viminal , Esquiline , Caelian and Aventine . These seven hills are not identical to the seven hills of the Septimontium (lat. Septem "seven" and mons "mountain, hill"), on which around 1000 BC. The Latins established the first settlements. The republic was established after the rule of seven kings.

### The seven in the Abrahamic world religions

Menorah, Bauhaus Weimar , 1922

#### The seven in Judaism

The number seven has a special position in the Jewish tradition. The Torah begins with the story of creation in seven days and contains many examples of the special uses of the seven. The Sabbath is the seventh day of the week, in the seventh year each follows the Schmittah year, the seven fat years followed in Joseph's interpretation of the dream of the Pharaohs, the seven lean years ( Gen 41  EU ), the sacred candelabra, the menorah has seven branches etc.

#### The seven in Christianity

In Christianity the seven also has its meaning; it is interpreted here as a combination of the divine trinity (three) with the four earthly elements. The Gospels tell of Jesus Christ seven last words on the cross and seven I-am-words . With the miraculous multiplication of bread, there are five loaves of bread and two fish that satisfy 4,000 people. In the Gospel of Matthew Jesus gives seven parables of the kingdom of heaven, in the Gospel of John seven miracles of Jesus are described. The Lord's Prayer consists of seven petitions.

In the Revelation of John , a letter to seven churches in which the Apocalypse is foretold, the seven is mentioned 54 times: the book with seven seals , the seven trumpets , each of which heralds another end-time apparition, seven bowls, seven Plagues , a seven-headed beast.

The pilgrim visited all seven Roman pilgrimage churches in a single day for a special indulgence. In early Christianity, the church father Tertullian is said to have referred to God as a sevenfold spirit who was the only one who shone in the dark, always holy: " septemplex spiritus, qui in tenebris unus lucebat, sanctus semper ".

Hieronymus Bosch (1450–1516): The Seven Deadly Sins ; (in the corners: the last four things )
The seven liberal arts , 15th century

In Catholicism there is a compilation of Pope Gregory the Great :

The Catholic Church also knows:

• seven sacraments :
• seven gifts of the Holy Spirit :
• Wisdom, understanding, advice, strength, science, piety, fear of God
• seven works of mercy :
• Eat the hungry, water the thirsty, accommodate strangers, dress the naked, care for the sick, visit prisoners, bury the dead
• seven sorrows of Mary :
• Presentation of Jesus in the temple with Simeon's prophecy , flight to Egypt, loss of the twelve-year-old Jesus in the temple, encounter between Jesus and his mother on the Way of the Cross , crucifixion of Jesus, deposition from the cross and delivery of the body to Mary [Pietà], burial of Jesus
• the seven joys of Mary:
• The Annunciation, the Visitation of the Virgin Mary, the birth of Jesus, the adoration of the kings, the twelve-year-old Jesus found again in the temple, the resurrection of Jesus, the Assumption of Mary into heaven with coronation.

Each of the seven gifts of the Holy Spirit corresponded to one of the seven liberal arts : grammar , rhetoric , dialectic , arithmetic , geometry , music , astronomy .

The seven different tones ( heptatonic ) of Gregorian chant were considered a perceptible expression of the world order.

##### Seventh-day Adventists and Seventh-day Baptists

At least two denominations officially name the seven as the number of the Sabbath : the Seventh-day Adventists and the Seventh-day Baptists . Here seven refers to the Sabbath (Saturday), the seventh day of the week, derived from Judaism , on which these churches worship .

#### Islam

The seven is also found in Islam . The Seventh Heaven is for Muslims the site of the last Transfiguration, the Prophet Mohammed reached. During the Hajj , the pilgrimage to Mecca , the Kaaba is walked around seven times in a counterclockwise direction. A principle of circular pilgrimages can be derived from this, in which seven graves of Islamic Sufi saints are visited in a specific order. The Seven Saints of Marrakech are an example of such a cult of saints .

This number seven is often interpreted as a synonym for infinity.

• John and Jesus (2nd heaven),
• Joseph (3rd heaven),
• Idris (4th heaven),
• Aaron (5th Heaven),
• Moses (6th heaven) and
• Abraham (7th heaven)

### The seven in modern Europe

In German-speaking countries, it is not ancient numerology, but it's everyday use if one of his belongings is asked or whether the seven senses have together. According to Endres, this is directly related to the Mithraic mystery, from which the Bible has taken elements. The question was put to the newly consecrated myths, they had to go through seven gates during the ceremony and take off an item of clothing and put it on again later. When there were several initiations, however, it was not easy to find your own belongings.

Andrian was of the opinion that the use of the seven can be proven as an import from abroad. In this way the seven develops in number superstition from the cosmic number, to the magic number and ultimately to the use or favorite number.

Above all the Germanic peoples have adopted the ideas about the mystical seven, mainly the southern Germanic peoples. In Thuringia, women with seven illegitimate children became “ virgins ” again. Brian McConnell, in an issue of the New Law Journal , said that in 1861 the 15-year prison sentence in Great Britain was not reduced for humanitarian reasons, but that fourteen is a multiple of seven.

Even today, the magic seven can be found in many fairy tales, proverbs, farmer wisdom and idioms. In fairy tales you can find the famous seven mile boots , the seven ravens and the seven dwarfs behind the seven mountains in Snow White. The brave little tailor does seven tricks in one go, and Max and Moritz handle seven tricks on Wilhelm Busch . Sindbad, the navigator of the Arab culture, had to endure adventure on seven journeys.

"If it rains on the dormouse (June 27th), seven weeks are blessed with rain."

- Peasant rule

Know-it-alls are called “seven clever ”. The "evil seven" has a different effect on events, in marriage " The darn 7th year " is at risk.

The assignment of the seven days of the week to the seven “planets” of ancient Babylon is also recognizable in today's languages: Sun to Sunday, Moon to Monday, Mars in Mardi (fr: Tuesday), Mercury in Mercredi (fr: Wednesday), the Jupiter in Giovedì (it: Thursday), Venus in Vendredi (fr: Friday) and Saturn in Saturday (en: Saturday).

It was sometimes added to meet the “sacred number of seven”. In order to obtain "seven seas", the Pacific and the Atlantic in north and south parts were counted. According to Giora, Newton's “seven colors” were probably supplemented by indigo for the “sacred number”. The “seven seas” and the “seven colors” are still in use today.

More often than not, car owners request license plates with number combinations of the 7.

### The seven in non-European cultures

• In Egypt , the seven plays a lesser role, but the main gods, Ra and Osiris , are surrounded by seven deities.
• The Nile flood also shows a seven-year, according to recent findings cycle on. This could refer to the seven fat and seven arid years in Egypt reported in the Bible.
• In the traditional and derived from it in the esoteric energy theory there are 7 main chakras , which are considered to be the main energy centers of humans.
• It is also a preferred number in India . The “seven cows of the highest heavenly regions” are venerated, and it is only in the seventh generation that the caste is changed to “above” or “below”.
• The number seven is the most common number in the Buddha- legends. The seven also has a special role in China .

## brand names

The number seven is included in brand names :

## literature

• Ferdinand Freiherr von Andrian-Werburg : The number seven in the spiritual life of the peoples . In: Mittheilungen der Anthropologische Gesellschaft in Wien , 1901, Volume 31, pp. 225-274.
• Erich Bischoff : The mysticism and magic of numbers (Arithmetic Kabbalah): numerical mysticism of the sky, music, nature, the human life course, history and spiritual life. Barsdorf, Berlin 1920; Edition Secret Knowledge, Graz 2013, ISBN 978-3-902881-49-6 .
• Ernst Bindel: The spiritual foundations of numbers: a lively introduction to the cultural history of numbers . Free Spiritual Life, Stuttgart 1958; Reprint: Anaconda, Cologne 2011, ISBN 978-3-86647-663-9 .
• Johann Heinrich Graf: The number “seven” . Wyss, Bern 1917 DNB 580888266 .
• B. McConnell: The secret seven . In: New Law Journal , 140, p. 1366. 1990.
• Ludwig Paneth: Number symbolism in the unconscious . Rascher, Zurich 1952 DNB 453696473 .
• Matthias Rochholz: Creation, enemy annihilation, regeneration. Investigation into the symbolic content of the power-charged number 7 in ancient Egypt . (Egypt and Old Testament 56). Munich, Wiesbaden 2002, ISBN 3-447-04604-X (also dissertation at the University of Mainz 2000).
• Reinhard Schlueter: Seven. A magic number . dtv , Munich 2011, ISBN 978-3-423-34640-5 .

Wiktionary: seven  - explanations of meanings, word origins, synonyms, translations
Wiktionary: Seven  - Explanations of meanings, word origins, synonyms, translations
Commons : Seven  - collection of images, videos and audio files

## Individual evidence

1. ^ Georges Ifrah, David Bellos, EF Harding, Sophie Wood and Ian Monk: The Universal History of Numbers: From Prehistory to the Invention of the Computer. London (Wiley & Sons), 1999. ISBN 9780471375685 .
2. Matthew Grissinger: Medication Errors - Misidentifi cation of Alphanumeric symbol Plays a Role in errors . P&T, Volume 42, Number 10, October 2017, pages 604-606. Available online as a PDF .
3. ^ Capella Rucellai by Alberti
4. a b c d L. Paneth: Number symbolism in the unconscious . Zurich 1952. (p. 194)
5. F. v. Andrian: The number seven in the spiritual life of peoples . In: Mittheilungen der Anthropologische Gesellschaft in Wien , Volume 31, pp. 225-274. 1901
6. Z. Giora: The Magical Number Seven . In: D. Robert (Ed.): Occident and Orient . Budapest 1988. p. 175 ff.
7. dtv Lexikon, 1990, Volume 17, p. 7
8. D. Forstner: The world of Christian symbols . Innsbruck 1986, p. 52
9. a b c d F. C. Endres: Mysticism and Magic of Numbers . Zurich 1951.
10. E. Bischoff: The mysticism and magic of numbers . Berlin 1920. p. 15
11. Die Ecliptik , The Celestial Table of Tal-Qadi , accessed on August 12, 2020
12. On the number seven , Die Himmelstafel von Tal-Qadi , accessed on August 12, 2020
13. M. Barthel: Shine and mystery of antiquity . Vienna, Düsseldorf 1992. p. 234
14. ^ S. Günther: History of Mathematics . Leipzig 1908. p. 11f
15. See Uhlig, 1976, p. 38
16. ^ J. Silver: Your lucky number. A modern magic of numbers . Geneva 1976
17. JH Graf: The number "seven" . Bern 1917, p. 17
18. ^ J. Silver: Your lucky number. A modern magic of numbers . Geneva 1976. p. 205
19. M. Vogel: The Nature Septime . Bonn 1991, pp. 42/43
20. Gen 41: 17-31