>>>>It's really unfortunate that some things end up becoming a debate. I prefer science. There is plenty of science involved in reading levels of text. There is Flesch-Kincaid grade level scoring built into MS Word.
>>>>
>>>>"The amount must be greater than or equal to zero." Reading level 4.8
>>>>
>>>>"The amount must not be negative." Reading level 7.6
>>>>
>>>>Clearly the second sentence is for a more sophisticated audience by almost 3 grade levels.
>>>
>>>I think most of our users will at least have high school diploma, so they'll understand what negative means :)
>>
>>I certainly hope that the person setting credit limits understands the difference between positive and negative numbers.
>
>Not necessarily, they only know the difference between credit and debit. To them a negative credit means a debit, and vice versa.

And then the accountant comes to slap them on the wrist, twist their ears and force them to kneel on corn: negative credit means cancelled credit entry, not debit. And vice versa. (At least that's what my tribe of accountants drilled into me)