Please Stop Saying That! (2024)

I think we all get annoyed at expressions that are over-used. A current one for me is “game changer”. But beyond being annoying, some common usages are downright wrong, especially when they purport to express mathematical ideas.

One example I have heard recently is people saying that something is “exponentially greater” than something else — say, that the number of Covid-19 cases is “exponentially greater” than it was last year. Mathematically that makes no sense. Exponential is a rate of change, not a difference. (Otherwise I could say that my earnings from Medium are exponentially greater this year than last year!) That is, a quantity may be growing exponentially, but it can’t just be exponential. Say “much larger” instead of “exponentially greater”.

Another example involves percentages. Recently I heard a political leader say that he would put “a thousand percent of my effort” into something. Percentages are really just fractional numbers — specifically fractions of 100. Fifty percent is 50/100, one-hundred percent is 100/100, and one thousand percent is 1000/100. So, while it’s possible to give 1000 percent (10 times) more of something (effort), it’s impossible to give 1000 percent of something. (Of course, 1000 percent can be used for comparison — your wealth may be 1000 percent of mine — but if I…