Probably with something like this:
>I would say the most likely correct construction would be DCCIV - seven hundred and four.
I’ve read that our modern use of IV was typically not used by the Romans, because it would be inviting trouble to drag Jupiter’s name into one’s banking. We consider J and I to be separate letters, likewise U and V. The Romans had not yet set aside J and U as proper letters, and JUpeter and IVpeter would have been undifferentiated. So, IV was a form of a god’s initials, and off limits for numbering. They would have used IIII.
I don’t have a cite or any evidence one way or the other on this, tho.
My Mom once showed me how to multiply roman numerals (like CXXVIII * CXCIX). I’ve blocked it out of my memory, it was rather horrid; it was a very compelling learn-from-experience way of getting the superiority of the Arabic system rather than just being told of it “as a fact”.
Ah, yeah, my bad, Napier, I misinterpreted what you said.
Captain Carrot, thanks, not to worry.
>My Mom once showed me how to multiply roman numerals (like CXXVIII * CXCIX).
I think this would be “compound arithmetic”, the method used for instance to add distances that are in miles, feet, and inches or to add angles that are in degrees, minutes and seconds. Something like a hundred years ago there was a commonly used math textbook by Pike, used to punish schoolchildren, or educate them in this valuable skill. I think the disuse of compound arithmetic ranks up there somewhere with the eradication of polio; not as severe an event, surely, but many more people suffered.
There is an anecdote in Suetonius’ life of the emperor Galba regarding a large inheritance Galba would have received but which then-emperor Tiberius reduced by deliberately misreading the Roman numerals in the will:
Several supplemental marks were used by Roman accountants when dealing with large numbers. An overhead bar, for example, indicated multiplication by 1000, while a variety of marks looking something like parentheses offered even higher multipliers. However, writers also wrote numerals with a long bar overhead simply to set them off from the rest of the prose; not to multiply, but simply to avoid having the letters mistaken for (parts of) actual Latin words. Writers therefore often followed different customs for showing large numbers in prose (see this site for a good explanation). Suetonius implies Tiberius took advantage of these discrepancies so that he could reinterpret the text of the will in a way more favorable to him (he was Livia’s son and so wanted to keep more of the inheritance for himself).
>I do, and nobody really seems to know.
Nice find, Tuckerfan!
Now, in this cite, E.L.F. does seem to think he knows, and that whatever author he read knew. The logic seems a little tangled up, because that conversation was about clock faces, and E.L.F. seems to have thoughtlessly said that the same reasoning I mention was the reason Roman clockmakers avoided “IV”. I presume on second thought he’d have corrected himself to say that Romans in general avoided “IV”, and the clockmaking theme had nothing to do with it, but rather just tripped him up.
There must be people who know, because there is plenty of Roman writing still around. We just haven’t found any of those people yet.
"The notation of Roman numerals has varied through the centuries. Originally, it was common to use IIII to represent four, because IV represented the Roman god Jupiter, whose Latin name, IVPPITER, begins with IV. The subtractive notation (which uses IV instead of IIII) has become universally used only in modern times. For example, Forme of Cury, a manuscript from 1390, uses IX for nine, but IIII for four. Another document in the same manuscript, from 1381, uses IV and IX. A third document in the same manuscript uses IIII, IV, and IX. "