Trivia :
In 2006, a reporter contacted me to confirm that it wasn't proper to advertise
the 2006 Super Bowl as "XXXX". The correct Roman numerals
(XL) were used for the rest of the advertising campaign.
Starting with Super Ball XLI, on February 4, 2007,
Numericana.com has received an abnormal number
of visits from football fans who take a sudden interest in Roman numerals
during Super-Bowl Sunday.
On a regular Sunday back then, we'd have been expecting about 1600 visits.
During Super-Bowl XLI, we had 4014...
The same phenomenon happens every year:
On the day of Super-Bowl XLII
(February 3, 2008) Numericana had 4824 visits.
For Superbowl XLIII
(February 1, 2009) 3447 visits were logged.
On Super Bowl XLIV
(February 7, 2010) 4803 hits were recorded.
On Feruary 6, 2011
(Super Bowl XLV)
all records were shattered,
in part because so many people were wondering why VL isn't a correct replacement for XLV...
Around kickoff time, our little server buckled under a peak load of one hit per second.
By the end of the day, we had logged 15278 queries (more than 90% of those about XLV).
That was more than three times the previous one-day record at Numericana...
This yearly frenzy caught the attention of Leanne Italie (Associated Press)
who interviewed me a week before Super Bowl XLVI.
Her story was picked up all over the place and inspired other articles,
included translations in
French
and
Chinese.
Super Bowl XLVI
took place on February 5, 2012 at Lucas Oil Stadium in Indianapolis.
When the dust settled, after the victory of the New-York Giants, all traffic records
had been shattered again at Numericana: 21399 hits in a single day
(midnight to midnight).
For Super Bowl XLVII (47) the traffic more than doubled again:
47237 visits in one day
(February 3, 2013). The stressed server worked flawlessly, so did the
counter.
On Sunday Feb. 2, 2014 (Superbowl XLVIII = 48) we "only" had 7157 hits
(just 15% of the all-time record from the previous year)...
Yet, it was our 4th busiest day in 14 years!
On Feb. 1, 2015, (Superbowl XLIX = 49) the Numericana site had 10974 visits,
9041 (82.4%) of those related to Roman numerals. A fair number of the football
fans were openly wondering why "IL" isn't a correct Roman number...
"Superbowl L" in February 2016 (year MMXVI)
was marketed as Super Bowl 50.
Roman numerals were used again for Super Bowl LI in 2017.
For Superbowl LII (4 Feb. 2018) we only had 1438 visits.
Any numeral is counted positively unless there's a larger numeral anywhere to its right,
in which case it is counted negatively.
However, proper Roman numbers are subject to the following restrictions
about the applicability of the subtractive principle.
The use of the subtractive principle has always been optional.
Its systematic use is fairly modern.
For example, it's acceptable to use IIII instead of IV, as is usually
done on clockfaces (to "balance" their left and right halves, so we're told).
The subtractive principle (a subtrahend preceding a minuend) may apply:
Only to a numeral (the subtrahend) that is a power of ten (I, X or C).
For example, "VL" is not a valid representation of 45 (XLV is correct).
Only when the subtrahend precedes a minuend no more than ten times larger.
For example, "IL" is not a valid representation of 49 (XLIX is correct).
Only if any numeral preceding the subtrahend is at least ten times larger.
For example, "VIX" is not a valid representation of 14 (XIV is correct),
and "IIX" is not correct for 8 (VIII is correct).
Only if any numeral following the minuend is smaller than the subtrahend.
For example, "XCL" is not a valid representation of 140 (CXL is correct).
When the second of the above conditions was not met in front of an M (or C) numeral,
a medieval convention was that the number to the left of M (or C) was the number
of thousands (or hundreds) which was to be added to the number located to
the right of M (or C). When this convention is intended, it's best to
write M (or C) as a superscript (as explained below).
For example, CM means 900, but LLM could only translate into 100000.
(This is a rather dubious example which is
not based on an historical instance.)
Do not assume that everyone is an expert at medieval numeration...
It's more likely that someone writing MXMI intends 1991,
rather than 1010001 = MX^{M}I.
A medieval writer would definitely have hesitated to use this
multiplicative convention beyond XCIXM (99000)
or XCIXMCMXCIX (99999).
Something like MIMIMI (1001001001)
would have sickened most medieval minds!
(2013-04-15)
Conversion from decimal numbers to Roman numerals.
A simple conversion table provides an easy, foolproof way.
All of the above rules for standard Roman numeration can be precisely
summarized by the following conversion table (for numbers up to 9999).
Matching multi-digit decimal numbers with their Roman counterparts :
Digit
Thousands
Hundreds
Tens
Units
0
1
M
C
X
I
2
MM
CC
XX
II
3
MMM
CCC
XXX
III
4
MMMM
CD
XL
IV
5
MMMMM
D
L
V
6
MMMMMM
DC
LX
VI
7
MMMMMMM
DCC
LXX
VII
8
MMMMMMMM
DCCC
LXXX
VIII
9
MMMMMMMMM
CM
XC
IX
For example, the Roman representation of 4096
is the juxtaposition of the "4" entry from the "thousands" column
(MMMM) the "9" entry from the "tens" (XC)
and the "6" entry from the "units" column (VI) :
4096 = MMMMXCVI
Likewise, you convert 2015 by concatenating MM, X and V :
2015 = MMXV
One last example: 1956 = M + CM + L + VI = MCMLVI.
For (much) larger numbers, read on...
kdomenick
(2001-04-02)
What are the Roman numerals for 18 034?
There are several correct answers for 18034, including the awkward:
MMMMMMMMMMMMMMMMMMXXXIV
The Roman system of numeration is based on an earlier Etruscan system which was sometimes
also used by the ancient Romans for slightly larger numbers.
The archaic symbol
used for 10000 was a large "m" with 5 legs instead of 3, and it may be typed as "((I))".
The symbol
for the number 100000 had 7 legs and may be typed as "(((I)))".
The obvious extension to 9 legs or more was apparently not used,
so the Roman representation of a million would consist of 10 times a 7-legged "m":
Incidentally, the right half of such symbols was used to represent half the corresponding
number.
For example, the numeral for 5000 was
, which may be typed as "I))".
The numeral for 500 was
, it could be typed as "I)",
but it got transliterated into "D", the same way
became "M" to represent
1000 (a mnemotechnical
bonus was that M is the initial of "mille", the Latin word for 1000).
In print or engravings, such archaic numbers often appear with a regular "C" instead of
our "(" and an upside-down "C" instead of our ")" (which is called an apostrophus
in this context), so that you will find
instead of "M" or ""
in the publication dates of some early books.
There are about a dozen (!) similar graphical variations on this archaic theme...
The basic rules of Roman numeration apply to such symbols:
Any numeral is counted positively unless there's a larger numeral anywhere to its right,
in which case it is counted negatively.
(As explained above, proper Roman numbers are subject to
precise restrictions when the numerals do not appear in decreasing order.)
Using the above Roman/Etruscan numerals for 10000 and 5000,
the number 18034 translates into:
MMMXXXIV
which could be typed
((I)) I)) MMMXXXIV
This archaic system was replaced by one which uses only
7 basic symbols
(I=1, V=5, X=10, L=50, C=100, D=500, M=1000),
with the convention that putting an overbar
(a vinculum) over a basic number
would denote a value 1000 times as large.
It became customary to add little downward-pointing corner marks to such a
multiplying vinculum because the straight vinculum was also used
(following the Greek custom) simply to distinguish numerals from regular letters,
within ordinary text.
Skipping that optional flourish, any Roman accountant would simply have expressed 18034 as:
XVIII
XXXIV
The convention about corner marks on the vinculum caused another problem:
If those marks were too large, the whole thing could be misread as an upper half-frame,
which indicated multiplication by 100000 instead!
This ambiguity is the source of a famous dispute about the testament of the widow
of Emperor Octavian (Livia Drusilla, 58 BC-AD 29) who willed either
500 000 or 50 000 000 sesterces
(most probably the latter) to the futur Emperor Galba,
whereas her son, the reigning Emperor Tiberius, was the residual heir.
The historian Suetonius reports that
quia notata non praescripta erat summa
(because the intended sum had not been written out in words),
Tiberius could rule that only the lesser amount was owed.
Suetonius adds that Galba did not even receive that!
The inscription in Livia's testament resembled the middle one below (she did use
"CCCCC" instead of the more compact "D" numeral):
CCCCC
CCCCC
CCCCC
500
or
500 000
500 000
or
50 000 000
50 000 000
Apparently, the historical record does not
show any instances of multiple overstrikes
to indicate successive multiplications by 1000
and/or 100 000 (stay away from this dubious
extension of the system).
When dealing with the very large amounts involved in public affairs,
the Romans understood that the "basic" unit was centena milia
(100 000, one hundred thousand [sesterces]).
As Emperor Vespasian took office in AD 69, the amount of money in the state
treasury was reported to him as quadringenties milies (400 times 1000 times)
namely: 40 000 000 000 sesterces.
Finally, as noted above,
it's worth mentioning that the familiar
subtractive principle
(according to which a numeral appearing before a higher one is to be counted negatively)
was not always strictly respected in medieval or ancient times.
Instead, smaller numerals appearing before M or C may have meant multiplication
(by 1000 or 100) instead, so that VIIC would mean 700 and VIM would mean 6000
(this is especially true in the context of
Common Era dates;
CE = Common Era = Christian Era = AD =
Anno Domini).
The unambiguous typography for this multiplicative convention is to put C or M as superscripts
(VII^{C} or VI^{M }),
which is consistent with ancient usage.
The use of a dot has also been advocated (VII.C or VI.M), but it is less than satisfying.
This gives yet another way to represent 18034, namely:
XVIII^{M}XXXIV
The (recommended) superscripting is not strictly necessary because the
unsuperscripted XVIIIMXXXIV wouldn't otherwise be a valid number...
psudo
(2002-03-01; e-mail)
Your discussion of roman numerals left me wondering if combinations
of superscripting and overstriking, say,
would be an acceptable stretch of the Roman system to represent larger numbers...
Extensions of Roman numeration have been toyed with, but
the historical record doesn't reveal any actual
usage of an extended system.
Multiple overstriking, or combinations of overstriking and superscripting,
are nowhere to be found, neither are multiple-legged symbols beyond
,
or equivalent parentheses combinations beyond (((I))).
I am not even sure whether overstriking was ever used with larger symbols like
(tell me).
Such extensions would be unambiguous enough to be interpreted correctly,
but they are just not a proper part of the system.
This used to be a genuine problem when Roman numeration was dominant in the
Western World.
That's no longer the case, though,
and there would be little point in devising a new extension to this antiquated
system, now best reserved to the mundane numbering of...
Bearers of the same name. (Popes, kings, family members, etc.)
Preface pages.
Book chapters.
Copyright years.
Superbowl events (at least up to XLIX = 49, in 2015).
Nothing beyond MMMCMXCIX (3999) is needed anytime soon.
(2013-04-15) Trivia Question
What year has required the longest string of Roman numerals, so far?
Answer: MDCCCLXXXVIII (1888). The record will be broken in 2888.
Nicholas Stevenson
(2002-10-07; e-mail)
I am currently translating the
Chronographus Anni CCCLIIII.
It has a few strange numbers like CCCLXIIS and LXXXVIIS
dealing with money and measurement.
I am not sure what the S represents [...]
"S" probably stands for "semis" (one half), however...
In both of your examples, we could also be dealing with the
abbreviation for sesterce "IIS"
(this later became "HS", which is better and less ambiguous).
This symbol comes from the fact that a sesterce was originally
two and a half asses
(when the as was still the primary Roman monetary unit).
If that's the case, CCCLXIIS
(or LXXXVIIS)
would be 360 (or 85) sesterces.
I think the abbreviation "IIS" was still
used when the "Chronography of 354" was written.
(Please tell me
whatever you may know.)
I thought about the money aspect of the symbol S, but it doesn't explain
what it means in terms of measurement.
I dont think that it is a symbol for
money, but perhaps it does mean half a denarius, or half a foot.
Here are both examples in full:
Congiarium dedit d LXXIIS.
[Where "d" replaces
the original symbol for denarii.]_{ }
... et oboliscum cum sua sibi
base, qui est in circo maximo, altum edes LXXXVIIS.
I just found something that probably explains it in one of my grammar
books: "As an abbreviation, S denotes sacrum, semis, sibi suis, etc."
I think S must [simply] mean a half.
Nick Stevenson
Right!
See below for other fractions used in Roman or Medieval times.
(2014-03-11) Duodecimal Roman fractions are all but forgotten.
Here's the rudimentary Roman representation of submultiples of unity.
One twelfth of a unit was an uncia ; one sixth of an
uncia was a sextula.
The names of most other Roman fractions
are given in the first column of the following table,
which appears on page 283 of the book Mathématiques et
mathématiciens (Editions Magnard, 1959) by
Pierre Dedron (1887-1970; ENS 1908) and
Jean Itard (1902-1979).
The second column gives the glyphs found in the works of
Victorius of Aquitaine
(fifth century AD).
The third column corresponds to the Basel edition (1558)
of the Latin translation of Euclid's Elements
by Johannes
Campanus of Novara (1220-1296).
The last two columns provide the ratio of the quantity to one whole unit and
to one ounce (1/12) respectively.
Libra Uncia
The smallest quantity expressible with the above Roman fractions is
the difference between a siliqua and a
chalcus, which amounts to 1/576
of an ounce (or 1/6912 of a whole).
The cerates, siliqua and chalcus are
respectively equal to 6, 4 and 3 times that elementary unit,
which has been called lentes (symbol unknown).
That forgotten unit was to a whole
( as or libra )
nearly what a grain is to a modern pound (1 lb is 7000 grains).
The ancient Romans never considered anything smaller than that.
The names of some small Latin fractions are loosely inspired by Greek
coins or weights. In ancient Athens, the equivalences were: