Let’s say you have a dozen gallons of ice cream (any flavor your want). Then something happens and all of a sudden you have 100 percent more. So now you have two dozen gallons of ice cream. That’s because the dozen new gallons equals 100 percent of what you started with.
Let’s say you start with a dozen gallons of ice cream. Then something happens and you have 100 percent less. That means you now have no ice cream at all. Because a dozen is 100 percent, and that’s how many gallons you’ve lost.
So how can you have 200 percent less, or 500 percent less, or 1,000 percent less? You can’t. It’s one of those irritating things about life. Once you have lost 100 percent of something, it’s all gone.
It’s the same way with “times.” If you start with a dozen gallons of ice cream and you end up with five times as much, you now have five dozen gallons of ice cream. But you can never end up with five times less, because that would mean getting rid of all your ice cream, plus four dozen gallons that you never had in the first place.
It’s also the same with distance. You can have something that’s five times farther away than it used to be. You can never have something that’s five time closer. Because as soon as it’s one time closer, it’s right on top of you.
Twice as bright? Sure. Twice as dim? No.
It’s amazing how many people don’t seem to get that, including scientific people who should have a lot of respect for numbers and feel comfortable around them. When I see writers playing fast and loose with numbers, I start wondering if they are as sloppy regarding all the other things they are writing about.
“OK, smart guy,” somebody out there is muttering, “What DO you have if it’s not five times less?”
If you had five of something and now you have one, you don’t have five times less (or even four times less, since you do still have one of them). What you have is one-fifth of what you started with. Or you have 20 percent of what you started with. Or you lost 80 percent of what you started with.
Bonus tip: If you are thinking of things in the aggregate, like ice cream, the word you want is “less.” If you are thinking of them in discrete units, like dishes of ice cream, the word you want is “fewer.”