Gematria is an Assyro-Babylonian system of numerology later adopted by Jews which assigns numerical value to a word or phrase, in the belief that words or phrases with identical numerical values bear some relation to each other, or bear some relation to the number itself as it may apply to a person's age, the calendar year, or the like. The best-known example of Gematria is the Hebrew word Chai ("alive"), which is composed of two letters which (using the assignments in the Mispar gadol table shown below) add up to 18. This has made 18 a "lucky number" among Jews, and gifts in multiples of 18 are very common.
Although the term is Hebrew, it most likely derives from Greek geōmetriā, "geometry", which was used as a translation of gēmaṭriyā, though some scholars believe it to derive from Greek grammateia, rather; it's possible that both words had an influence on the formation of the Hebrew word. (Some also hold it to derive from the order of the Greek alphabet, gamma being the third letter of the Greek alphabet (gamma + tria).) The word has been extant in English since the 17th century from translations of works by Giovanni Pico della Mirandola. Although ostensibly derived from Greek, it is largely used in Jewish texts, notably in those associated with the Kabbalah.
Some identify two forms of gematria: the "revealed" form, which is prevalent in many hermeneutic methods found throughout Rabbinic literature, and the "mystical" form, a largely Kabbalistic practice.
Though gematria is most often used to calculate the values of individual words, psukim (Biblical verses), Talmudical aphorisms, sentences from the standard Jewish prayers, personal, angelic and Godly names, and other religiously significant material, Kabbalists use them often for arbitrary phrases and, occasionally, for various languages. A few instances of gematria in Arabic, Spanish and Greek, spelled with the Hebrew letters, are mentioned in the works of Rabbi Abraham Abulafia; some Hasidic Rabbis also used it, though rarely, for Yiddish. However, the primary language for gematria calculations has always been and remains Hebrew and, to a lesser degree, Aramaic.
רבי אלעזר בן חסמא אומר, קנין ופתחי נדה הן הן גופי הלכות. תקופות וגמטריאות פרפראות לחכמה.
Rabbi Eleazar Chisma said: the laws of mixed bird offerings and the key to the calculations of menstruation days—these, these are the body of the halakhah. The calculation of the equinoxes and gematria are the desserts of wisdom.
An alternative translation to the Hebrew word פרפראות is "minor side dishes".
Minor dishes may be served before, during, or after a meal, to add interest and variety; they are the appetizers, side dishes, desserts, tid-bits — never to be served as main dishes. In other words, these sciences, while important, are yet only auxiliary and secondary. What is primary is the Torah. What is central is the life-giving law.
The value of the Hebrew vowels is not usually counted, but some lesser-known methods include the vowels as well. The most common vowel values are as follows (a less common alternative value, based on digit sum, is given in parentheses):
Sometimes the names of the vowels are spelled out and their gematria is calculated using standard methods.
There are several methods used to calculate the numerical value for the individual words, phrases or whole sentences. More advanced methods are usually used for the most significant Biblical verses, prayers, names of God and angels etc.
Mispar Hechrachi (absolute value) that uses full numerical value of the twenty-two letters. Sometimes its also called Mispar ha-Panim (face number), as opposed to the more complicated Mispar ha-Akhor (back number).
Mispar Gadol counts the final forms (sofit) of the Hebrew letters as a continuation of the numerical sequence for the alphabet, with the final letters assigned values from 500 to 900.
The same name, Mispar ha-Gadol, is also used for another method, which spells the name of each letter and adds the standard values of the resulting string.
Mispar Katan calculates the value of each letter, but truncates all of the zeros. It is also sometimes called Mispar Me'ugal.
Mispar Siduri (ordinal value) with each of the 22 letters given a value from one to twenty-two.
Mispar Bone'eh (building value, also Revu'a, square) is calculated by walking over each letter from the beginning to the end, adding the value of all previous letters and the value of the current letter to the running total. Therefore, the value of the word "Achad" (one) is 1 + (1 + 8) + (1 + 8 + 4) = 23.
Mispar Kidmi (triangular value) uses each letter as the sum of the all the standard gematria letter values preceding it. Therefore, the value of Aleph is 1, the value of Bet is 1 + 2 = 3, the value of Gimmel is 1+2+3=6, etc. It's also known as Mispar Meshulash (triangular or tripled number).
Mispar P'rati calculates the value of each letter as the square of its standard gematria value. Therefore, the value of Aleph is 1 × 1 = 1, the value of Bet is 2 × 2 = 4, the value of gimmel is 3 × 3 = 9, etc. It's also known as Mispar ha-Merubah ha-Prati'.
Mispar ha-Merubah ha-Klali is the square of the standard absolute value of each word.
Mispar Meshulash calculates the value of each letter as the cube of their standard value. The same term is more often used for Mispar Kidmi.
Mispar ha-Akhor The value of each letter is its standard value multiplied by the position of the letter in a word or a phrase in either ascending or descending order. This method is particularly interesting, because the result is sensitive to the order of letters. It's also sometimes called Mispar Meshulash (triangular number).
Mispar Mispari spells out the standard values of each letter by their Hebrew names ("Achad" (one) is 1+8+4=13 etc.), and then adds up the standard values of the resulting string.
Mispar Shemi (also Millui letter "filling"), uses the value of each letter as equal to the value of its name. For example, the value of the letter Aleph is (1 + 30 + 80) = 111, Bet is (2 + 10 + 400) = 412, etc. Sometimes the same operation is applied two or more times recursively.
Mispar Ne'elam (hidden number) spells out the name of each letter without the letter itself (e.g. "Leph" for "Aleph") and adds up the value of the resulting string.
Mispar Katan Mispari (integral reduced value) is used where the total numerical value of a word is reduced to a single digit. If the sum of the value exceeds 9, the integer values of the total are repeatedly added to produce a single-digit number. The same value will be arrived at regardless of whether it is the absolute values, the ordinal values, or the reduced values that are being counted by methods above.
Mispar Misafi adds the number of the letters in the word or phrase to their gematria.
Kolel is the number of words, which is often added to the gematria. In case of one word, the standard value is incremented by one.
Within the wider topic of Gematria are included the various alphabet transformations where one letter is substituted by another based on a logical scheme:
Atbash uses exchanges each letter in a word or a phrase by opposite letters. Opposite letters are determined by substituting the first letter of the Hebrew alphabet (Aleph) with the last letter (Tav), the second letter (Bet) with the next to last (Shin), etc. The result can be interpreted as a secret message or calculated by the standard gematria methods. A few instances of Atbash are found already in the Hebrew Bible. For example, see Jeremiah 25:26, and 51:41, with Targum and Rashi.
Albam the alphabet is divided in half, eleven letters in each section. The first letter of the first series is exchanged for the first letter of the second series, the second letter of the first series for the second letter of the second series and so forth.
Achbi divides the alphabet into two equal groups of eleven letters. Within each group, the first letter is replaced by the last, the second by the tenth, etc.
Ayak Bakar replaces each letter by another one that has a 10-times-greater value. The final letters usually signify the numbers from 500 to 900. Thousands is reduced to ones (1000 becomes 1, 2000 becomes 2 etc.)
Ofanim replaces each letter by the last letter of its name (e.g. "Fe" for "Aleph").
Akhas Beta divides the alphabet into three groups of 7, 7 and 8 letters. Each letter is replaced cyclically by the corresponding letter of the next group. The letter Tav remains the same.
Avgad replaces each letter by the next one. Tav becomes Aleph. The opposite operation is also used.
Some authors provide lists of as many as 231 various replacement ciphers, related to the 231 mystical Gates of the Sefer Yetzirah.
Dozens of other far more advanced methods are used in Kabbalistic literature, without any particular names. In Ms. Oxford 1,822, one article lists 75 different forms of gematria. Some known methods are recursive in nature and are reminiscent of the graph theory or use heavily combinatorics. Rabbi Elazar Rokeach often used multiplication, instead of addition, for the above-mentioned methods. For example, spelling out the letters of a word and then multiplying the squares of each letter value in the resulting string produces very large numbers, in orders of trillions. The spelling process can be applied recursively, until a certain pattern (e.g. all the letters of the word "Talmud") is found; the gematria of the resulting string is then calculated. The same author also used sums of all possible unique letter combinations, which add up to the value of a given letter. For example, the letter Hei, which has the standard value of 5, can be produced by combining 1 + 1 + 1 + 1 + 1, 2 + 1 + 1 + 1, 3 + 1 + 1, 4 + 1, 2 + 2 + 1 or 2 + 3, which adds up to 30. Sometimes combinations of repeating letters are not allowed (e.g. 2 + 3 is valid, but 3 + 1 + 1 is not). The original letter itself can also be viewed as a valid combination.
Variant spellings of some letters can be used to produce sets of different numbers, which can be added up or analyzed separately. Many various complex formal systems and recursive algorithms, based on graph-like structural analysis of the letter names and their relations to each other, modular arithmetic, pattern search and other highly advanced techniques, are found in the "Sefer ha-Malchuth" by Rabbi David ha-Levi of Draa Valley, a Spanish-Moroccan Kabbalist of the 15–16th century. Rabbi David ha-Levi's methods take into consideration the numerical values and other properties of the vowels as well.
Kabbalistic astrology uses some specific methods to determine the astrological influences on a particular person. According to one method, the gematria of the person's name is added to the gematria of his of her mother's name; the result is then divided by 7 and 12. The remainders signify a particular planet and Zodiac sign.
The most common form of gematria is used in the Talmud and Midrash, and elaborately by many post-Talmudic commentators. It involves reading words and sentences as numbers, assigning numerical instead of phonetic value to each letter of the Hebrew alphabet. When read as numbers, they can be compared and contrasted with other words or phrases – cf. the Hebrew proverb נכנס יין יצא סוד (nichnas yayin yatza sod, lit. "wine entered, secret went out", i.e. "in vino veritas"). The gematric value of יין ("wine") is 70 (י=10; י=10; ן=50) and this is also the gematric value of סוד ("secret", ס=60; ו=6; ד=4).
Use in other languages
The first attested use of gematria occurs in an inscription of Assyrian ruler Sargon II (727–705 BC) stating that the king built the wall of Khorsabad 16,283 cubits long to correspond with the numerical value of his name. Gematria or isopsephy was borrowed into the Greek probably soon after their adoption of the Semitic writing system. The extant examples of use in Greek come primarily for the Christian literature and, unlike rabbinic sources, is always explicitly stated as being used. It has been asserted[where?] that Plato (c. 427-347 BC) offers a discussion of gematria "in its simplest forms" in the Cratylus, where he is said to have claimed that "the 'essential force' of a thing's name is to be found in its numerical value, and that words and phrases of the same numerical value may be substituted in context without loss in meaning." A direct review of the Cratylus, however, shows that Plato made no such claim and that gematria is not discussed in it either explicitly or implicitly. What can be more accurately stated is that Plato's discussion in the Cratylus involves a view of words and names as referring (more or less accurately) to the "essential nature" of a person or object, and that this view may have influenced – and is central to – Greek gematria.
The Latin-script languages exhibit borrowing of gematria methods dating from the early Middle Ages after the use lapsed following the collapse of the Roman Empire in the 5th century.
Many researchers connect the "Number of the Beast", referred to in the Book of Revelation of the New Testament, with either Greek or Hebrew gematria as used by the early Christians. According to such interpretations, the number in question, 666, was originally derived via gematria from the name of the Roman emperor of the time, Nero Caesar (נרונקסרNero Qasr).
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The Gematria Database at Esoteric Delights is a large online gematria database (over 235,000 translations) of the Hebrew–English dictionary, along with tools for transliteration and translation, geared towards English-speaking esoteric communities.