🏛️Elementary Latin Unit 7 – Numerals and Counting

Latin numerals and counting are essential for understanding ancient texts and inscriptions. This system uses letters to represent numbers, with cardinal numbers expressing quantity and ordinal numbers indicating sequence. Mastering these concepts opens up a world of Roman literature and culture. Numbers in Latin have unique declensions and usage rules. Unus, duo, and tres decline irregularly, while other numbers are indeclinable. Proper placement and agreement with nouns are crucial for constructing grammatically correct sentences. Understanding these rules enhances Latin comprehension and composition skills.

Key Concepts

  • Latin uses a unique numeral system based on letters to represent numbers
  • Cardinal numbers express quantity or "how many" of something (unus, duo, tres)
  • Ordinal numbers indicate sequence or order (primus, secundus, tertius)
  • Numbers can be declined, meaning their endings change based on grammatical function in a sentence
    • Unus, una, unum (one) declines like a first and second declension adjective
    • Duo (two) and tres (three) have irregular declensions
  • Latin numbers are placed before the noun they modify, unlike in English where they typically come after (decem puellae vs. ten girls)
  • Certain numbers, when used with specific nouns, can have idiomatic or special meanings (Tres Gratiae - The Three Graces)
  • Practicing declension, translation, and usage of numbers in context is key to mastering this concept

Roman Numeral System

  • Latin uses seven letters to represent numbers: I (1), V (5), X (10), L (50), C (100), D (500), M (1000)
  • Combinations of these letters are used to create all other numbers
    • Placing a smaller numeral before a larger one indicates subtraction (IV = 4, IX = 9)
    • Placing a smaller numeral after a larger one indicates addition (VI = 6, XI = 11)
  • A bar over a numeral multiplies its value by 1,000 (V̅ = 5,000, M̅ = 1,000,000)
  • Numerals are typically written largest to smallest from left to right (MMXXII = 2022)
  • The subtractive principle is generally used only with powers of ten (IV, IX, XL, XC, CD, CM)
  • Repeating a numeral up to three times indicates addition (III = 3, XXX = 30, CCC = 300)
  • There is no concept of zero or negative numbers in the Roman system

Cardinal Numbers

  • Cardinal numbers are used to express quantity or "how many" of something
  • The numbers 1-10 in Latin are: unus, duo, tres, quattuor, quinque, sex, septem, octo, novem, decem
  • Numbers 11-17 are formed by adding the appropriate digit to 10 (undecim, duodecim, tredecim, etc.)
  • 18 is expressed as "duodeviginti" (literally "two from twenty") and 19 as "undeviginti" ("one from twenty")
  • Decades 20, 30, 40... 90 are: viginti, triginta, quadraginta, quinquaginta, sexaginta, septuaginta, octoginta, nonaginta
  • Hundreds 100, 200, 300... 900 are: centum, ducenti, trecenti, quadringenti, quingenti, sescenti, septingenti, octingenti, nongenti

Ordinal Numbers

  • Ordinal numbers are used to express sequence or order (first, second, third, etc.)
  • Most ordinal numbers are formed by adding -us, -a, -um to the cardinal number
    • 1st: primus, 2nd: secundus, 3rd: tertius, 4th: quartus, 5th: quintus...
  • Unus (one) has no corresponding ordinal; primus (first) is used instead
  • Some ordinal numbers have irregular forms (secundus vs. duo, tertius vs. tres)
  • Ordinals decline like regular first and second declension adjectives to match the noun they modify
    • Primus liber (first book), prima puella (first girl), primum verbum (first word)
  • They typically precede the noun, but can also follow for emphasis or in certain idiomatic phrases

Declension of Numbers

  • The cardinal numbers unus (one), duo (two), and tres (three) are declined
  • Unus declines like a first and second declension adjective with -us, -a, -um endings
    • Nom: unus, una, unum; Gen: unius; Dat: uni; Acc: unum, unam, unum; Abl: uno, una, uno
  • Duo has separate masculine, neuter, and feminine forms, while tres only differs in the neuter nominative/accusative
    • Duo (m./n. nom/acc), duae (f. nom.), duorum (m./n. gen.), duarum (f. gen.), duobus (m./n. dat/abl), duabus (f. dat/abl)
    • Tres (m./f. nom/acc), tria (n. nom/acc), trium (gen.), tribus (dat./abl.)
  • All other numbers through 100 are indeclinable, meaning they do not change form
  • Numbers 200 and higher are declined like the plural of their corresponding noun (ducenti, -ae, -a)

Using Numbers in Sentences

  • Cardinal numbers typically precede the noun they modify and agree with it in case
    • Decem (nom.) puellae (nom.) in horto sunt. (Ten girls are in the garden.)
    • Puer cum tribus (abl.) amicis (abl.) ludit. (The boy plays with three friends.)
  • Mille (thousand) can be either an indeclinable adjective or a neuter noun
    • Mille (indecl.) milites (nom.) in castra venerunt. (A thousand soldiers came into the camp.)
    • Tria milia (nom. pl.) militum (gen. pl.) in castra venerunt. (Three thousand of soldiers came into the camp.)
  • Ordinal numbers are used to indicate rank, sequence or order
    • Primus (nom.) ad metam pervenit. (He arrived first to the finish line.)
    • Anno sexto (abl.) decimo (abl.), bellum finitum est. (In the sixteenth year, the war was finished.)

Common Latin Number Phrases

  • Certain Latin number phrases have special idiomatic meanings beyond their literal translation
  • Unus pro omnibus, omnes pro uno. (One for all, all for one.)
  • In medias res (Into the middle of things - starting a story in the midst of action)
  • Tres Gratiae (The Three Graces - minor goddesses of charm, beauty, and creativity in Greek/Roman myth)
  • Duo fulmina belli (Two thunderbolts of war - referring to two great generals)
  • Duo cum faciunt idem, non est idem. (When two do the same thing, it is not the same thing.)
  • E pluribus unum (Out of many, one - motto on the Great Seal of the United States)
  • Nulla dies sine linea (No day without a line - an artist or writer should create every day)

Practice and Application

  • Memorize the cardinal numbers 1-10 and practice basic math problems in Latin
  • Decline unus, duo, and tres in all cases to master their irregular forms
  • Practice translating simple Latin sentences with numbers, focusing on noun-adjective agreement
    • Quattuor canes in via currunt. (Four dogs run in the street.)
    • Septem diebus mundum Deus creavit. (In seven days God created the world.)
  • Learn common Latin number phrases and practice using them in context
  • Create your own practice sentences using a variety of numbers, cases, and genders
  • Read authentic Latin texts that incorporate numbers to see them used in genuine contexts
    • Fabulae (stories), historiae (histories), epigrammata (epigrams)
  • Explore how Latin number concepts influenced English and other modern languages


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© 2024 Fiveable Inc. All rights reserved.
AP® and SAT® are trademarks registered by the College Board, which is not affiliated with, and does not endorse this website.