‘The problem with the advice you got about writing with numbers is that the wording was ambiguous. Also it had a comma splice in it, which was confusing. Here is the advice in correctly punctuated form, edited for clarity: Spell out numbers from zero to nine, and use numerals for numbers 10 and up, except when the number comes at the beginning of the sentence. If you need to start a sentence with a number, always spell out the number, no matter how high it is.

Although that’s sound advice in most cases (especially in journalism and the Social Sciences), the issue is complicated.  For example, the Modern Language Association advises us to spell out all numbers one hundred and below and use numerals for 101 and above.  But they make exceptions for very large round numbers, such as a forty million, which should be spelled out. Seems reasonable.

Diana Hacker (author of A Canadian Writer’s Reference) advises that, no matter which system you are using, you should be consistent within a sentence (but I have noticed in newspapers and magazines that journalists will mix numerals with spelled-out numbers in a sentence).

Diana also says we should mix it up when one number follows another, to avoid confusion. The examples she gives are “three 100-metre events” and “25 four-poster beds.”

If you have to start a sentence with a very large number, Diana advises, rewrite the sentence!

Just getting back in practice to resume teaching this week. No doubt you know all this already and were just being “ironic” in your email. If you would like a dissertation on the use of quotation marks for the sake of “irony,” let me know.’

- a University of Winnipeg professor