This makes me crazy, but there must be a good reason this is done. Is there really anyone who doesn't know that "two" is "2" or "three" is "3"?
I mostly see it on legal documents, but in many others as well. Is it a old style of writing that keeps finding its way into modern writing, or is it really still correct, and I'm wrong?
Janis said:
...but there must be a good reason this is done.
Don't be too sure about that! There may have been a reason at one time (in the days when all documents were written out in longhand?), but I agree that it doesn't make sense anymore. Legal documents, unfortunately, are known for meaningless, archaic usages. (One of my favorites: "ss," meaning... well, no one seems to know.)
Good question, Janis. In Garner's Modern American Usage, Bryan Garner (an expert on legal writing) says that this convention harks back to the time when legal scribes spelled out numbers so they couldn't be fraudulently altered. (I guess the way a clever student might just add a little line to that report card making the "F" an "A.") Much harder to do that in the pre-whiteout and pre-photocopying days if you spelled out the name of the number as well. He says, btw, that this convention should remain in the realm of legal writing and that even there, as you suggest, it's often unnecessary.
I can see how the word one would follow the number 1, as the number could be altered to a 4 (likewise some other numbers, like 16 to 48), and others, but never the other way around.
The majority of the gobbledy gook that we call legalese is simply the avoidance of doubt. I've participated in many contract negotiations where the bulk of the discussion is not whether both parties are okay with the terms, but whether both parties clearly understand the terms.
I sat in one discussion where a five minute argument over whether to use Product Assurance or Quality Assurance was resolved when someone said, "I think we both mean the same thing. Can we include both terms and a definition?" - so everyone agrees and there's one less reason to go to court later, but as a consequence, the contract becomes longer and - to some - more incomprehensible.
Regardless of how it may have started, I think the practice of writing numbers two different ways persists because it avoids doubt.