Roman Numeral Curiosities
Fascinating facts about the numbering system that has survived thousands of years
Roman Numerals - More Than Just I, V, X
Roman numerals are one of the oldest number notation systems that continue to fascinate us today. While most of us know the basic symbols like I, V, X, L, C, D, and M, this system hides many surprising secrets and curiosities that are not commonly known.
From unusual notation rules to forgotten symbols used in antiquity - the history of Roman numerals is full of surprises. In this article, we will discover these lesser-known aspects of the numbering system that has left an indelible mark on our civilization and culture.
The curiosities below will not only expand your knowledge but also allow you to look at the familiar system from a completely new perspective. Some of them may completely change your understanding of Roman numerals!
Quick: 5 surprising facts
- Romans did not know the digit zero
- The symbol "N" was used to write the number 90 in the Middle Ages
- IIII instead of IV on clock faces is tradition, not error
- Romans used fractions based on twelves
- The digit "M" comes from the word "mille" (thousand)
Surprising Facts About Roman Numeral Notation
1. Absence of Zero in the Roman System
One of the most surprising curiosities is the fact that the Roman system did not have a symbol denoting zero. Unlike the Arabic system, where zero plays a key role, Romans did not recognize zero as a number. In their philosophy and mathematics, there was no concept of "nothingness" as a numerical value.
Instead of using zero, Romans simply omitted non-existent values. For example, the year 2023 is MMXXIII, without the need to mark the absence of hundreds. This is one of the reasons why the Arabic positional system eventually displaced the Roman system in more complex mathematical calculations.
The word "nulla"
Although Romans did not have a symbol for zero, they had a word for "nothing" - nulla. In later mathematical texts, this word was sometimes used to denote absence of value, but it never became part of the standard number notation system.
It was not until the 12th century, thanks to the work of mathematician Fibonacci, that zero was introduced to European mathematics along with the Arabic system.
2. IIII vs IV - Two Correct Forms of Notation
On many antique clocks and buildings, we can notice the number 4 written as IIII, not IV. Contrary to popular belief, both forms of notation were used in ancient Rome and both are historically correct.
The additive form (IIII) was commonly used in the early period, while the subtractive form (IV) appeared later. On clock faces, the IIII notation was traditionally maintained for several reasons:
Why IIII on clocks?
- Visual balance - IIII balances better with VIII on the opposite side of the dial
- In ancient times Jupiter was written as IVPP - IV was avoided out of respect for the god
- Clockmaking tradition - IIII was easier to cast in metal than IV
- Group symmetry - with IIII on the dial you can create 4 groups of digits with similar number of characters
3. Limitations of the Subtraction Rule
Many people think that in Roman numerals every smaller digit placed before a larger one means subtraction. In reality, the subtraction rule has strict limitations that are not commonly known:
Rule 1
Only one symbol can be subtracted at a time. Therefore 8 is VIII, not IIX. IX (9) is correct, but not IIX (8).
Rule 2
A symbol can only be subtracted from the two next larger values. I can only be subtracted from V and X, not from L or C.
Rule 3
Only symbols I, X and C can be used as subtracted digits. D and L never appear in the "subtracted" position.
According to these rules, correct notations are: IV (4), IX (9), XL (40), XC (90), CD (400), CM (900). However, incorrect would be notations like: IL (49), XM (990), or VL (45).
Forgotten Aspects of Roman Numerals
4. Roman Fractional System
Few people know that Romans had an elaborate fractional notation system that differed significantly from our contemporary one. The Roman fractional system was based on twelves (duodecimal), not tens like the modern system.
The basic unit was as (whole), which was divided into 12 unciae. Each uncia had its own symbol and name. This system was particularly useful in trade, as 12 can be easily divided by 2, 3, 4, and 6.
Selected Roman fractions
5. Forgotten Numerical Symbols
At different periods in history, additional numerical symbols appeared that did not survive to our times or are rarely used:
Apostrophic Symbol
Ancient Romans used the symbol ↀ or (I) to denote 1000, and the symbol (I) for 500. This notation used parentheses instead of the letters M and D.
Symbol N for 90
In some medieval manuscripts, you can find the symbol N used to denote the number 90, instead of the standard XC. It came from the Latin word "nonaginta".
Vinculum
For very large numbers, Romans used a horizontal line (vinculum) above the symbol, which meant multiplication by 1000. For example, V̅ meant 5000.
6. Origins of Roman Symbols
The symbols used in Roman numeral notation have fascinating origins that are not always obvious:
Etruscan theory
Some historians believe that Roman numerical symbols derive from the Etruscan numbering system. The symbol 'Λ' (similar to V) meant 5, and 'X' was created by overlaying two 'Λ' symbols.
The symbol I was the simplest designation of a unit - a single stroke. The symbol C (100) most likely comes from the first letter of the Latin word "centum" (hundred).
Hand gesture theory
Another theory suggests that some symbols arose from hand gestures used in counting. The symbol V represents the spread fingers of one hand (5), and X is two crossed hands (10).
The symbol L (50) could initially be written as half of the symbol C, and D (500) as half of the symbol M, which would explain their values as halves of "neighboring" larger digits.
Curiosity: The longest Roman number
Because the Roman system is not positional, some numbers can have an exceptionally long notation. For example, the number 1888 written in the Roman system is MDCCCLXXXVIII - it contains as many as 13 characters!
For comparison, the same number in the Arabic system takes only 4 digits. This is one of the practical disadvantages of the Roman system that contributed to its replacement by the Arabic system in everyday calculations.
Roman Numerals in Unexpected Places
7. Super Bowl and Roman Numerals
Super Bowl, the championship game of American football, is one of the few modern sporting events that consistently uses Roman numerals to designate its editions. Since Super Bowl V in 1971, each edition has been marked with Roman numerals.
A funny deviation was Super Bowl 50 in 2016, which was initially supposed to be designated as "Super Bowl L". However, organizers decided that the single letter "L" would not look good from a marketing perspective, so they exceptionally used the Arabic numeral "50". The following year they returned to tradition with "Super Bowl LI".
8. Roman Numerals in Cinematography
Hollywood film studios have a long tradition of using Roman numerals in end credits to denote the year of film production. This custom dates back to the early days of cinema and was meant to give films a more classical, prestigious appearance.
Many film series, such as "Star Wars", "Rocky" or "Rambo" also use Roman numerals to number subsequent parts, instead of Arabic numerals.
Examples of films with Roman numbering:
- Star Wars: Episode IV - A New Hope (1977)
- Rocky III (1982)
- The Godfather Part II (1974)
- Final Destination V (2011)
- Saw VI (2009)
9. Unusual Applications of Roman Numerals
Roman numerals appear in many unexpected places:
Electoral District Designations
In many countries, electoral districts are numbered with Roman numerals, which is a continuation of administrative tradition dating back to ancient times.
Degrees of Kinship
In canon and civil law, degrees of kinship are often marked with Roman numerals, determining the genealogical distance between relatives.
Cipher Symbols
Roman numerals were used in historical cryptography. The Caesar cipher, one of the oldest known ciphers, was described using shifts expressed in Roman numerals.
Mathematical Curiosities About Roman Numerals
10. Mathematical Limitations of the Roman System
The Roman system, despite its historical value, has serious mathematical limitations that make it impractical for advanced calculations:
Lack of Positionality
Unlike the Arabic system, the value of a Roman symbol does not depend on its position in the number. This makes basic operations like multiplication or division very complicated.
Problem with Large Numbers
The Roman system becomes unwieldy when writing large numbers. A million is MMMM repeated 250 times or M with a line, indicating multiplication by 1000.
These limitations are the main reason why Romans used numbers primarily for recording, not for calculations. For calculations, they used special tools, such as counting boards and abacuses, which enabled more efficient mathematical operations.
11. Roman Calculator - Abacus
Despite the limitations of the notation system, Romans were excellent practical mathematicians. Their secret weapon was the Roman abacus - a device for performing calculations that compensated for the shortcomings of the number writing system.
The Roman abacus consisted of a frame with grooves in which pebbles or tokens were placed. Each groove represented a different order of magnitude (units, tens, hundreds, etc.). Thanks to this device, Romans could perform complex calculations that would be extremely difficult using only the Roman numeral notation system.
Abacus curiosity
The Roman abacus was so effective that similar devices were used in Europe until the 17th century, long after the fall of the Roman Empire. Roman accountants and tax collectors could perform calculations on it with amazing speed.
The word "calculator" comes from the Latin word "calculus", meaning small pebble - exactly the kind used for counting on the abacus.
12. Largest Known Roman Number in Ancient Inscriptions
On some ancient monuments, you can find impressive records of very large numbers. Inscriptions on Trajan's Column in Rome contain some of the largest Roman numbers that have survived to our times.
For really large numbers, Romans sometimes used a combination of symbol and word, for example "C M" meant "one hundred thousand" (centum milia). Numbers larger than a million were rarely used, but if necessary, they used descriptive terms like "decies centena milia" (ten times one hundred thousand) for a million.
Notation for large numbers:
Frequently Asked Questions About Roman Numerals
Are Roman numerals still officially used in any country?
Roman numerals are no longer the official numbering system in any country, but they are used in official Vatican documents, which continues the tradition of their use in many official contexts.
Is there a largest possible Roman numeral?
Theoretically, the Roman system has no upper limit. By adding more and more M symbols, you can represent increasingly larger numbers. For convenience, large numbers were marked with a line above the symbol (M̅ = 1,000,000) or descriptive Latin terms were used.
Why are some Roman numerals subtracted and others added?
The subtraction rule (e.g., IV instead of IIII) was introduced later to shorten the notation of some numbers. Originally, all symbols were added. This rule follows strict rules - only digits I, X and C can be subtracted and only from the two nearest larger symbols.
Can Roman numerals represent negative numbers?
The classical Roman numeral system did not have the concept of negative numbers. In ancient Rome, negative numbers were not used in everyday calculations, and operations on debts were expressed descriptively, not with symbols.