# Has the illogical "three times bigger" replaced "three times as big" in common usage?

If A is one time bigger than B, it is equal to 2B. So if A is three times bigger than B, it is equal to 4B. Yet I am seeing "two times bigger" to mean "twice as large" in more and more places.

Any insights?

• All English idioms are not mathematically sound. Jan 13, 2015 at 20:01
• This is discussed at the “X times as many as” or “X times more than” thread. Jan 13, 2015 at 20:27
• @PeterShor - GoPats - should I interpret your comment to mean that none are mathematically sound, or that only some are so?
– user98990
Jan 14, 2015 at 4:46

While we can't make a claim as to the specific intended meaning, we see that usage of "three times as big" has rapidly declined since the 1940s, while usage of "three times bigger" has simultaneously increased.

It is safe to say that "three times bigger" is acceptable (whatever its meaning), but it has not (yet) replaced "three times as big".

• I think it's quite probable that people saying "a third larger" mean "four thirds as large", but when they say "three times larger" they mean "three times as large". Note that a third larger is decreasing in usage; if it disappears, "three times larger" won't be ambiguous. Jan 13, 2015 at 20:34
• 'It is safe to say that "three times bigger" is acceptable (whatever its meaning)' is arguable. Many people are certainly happy to use it in the threefold rather than fourfold sense, but I wouldn't like to argue that that usage is considered 'acceptable' in a legal document. In maths, 'scale factors' and '%ge increases' are used to avoid confusion. Jan 13, 2015 at 20:59
• @EdwinAshworth I never meant to imply that "acceptable" means "legally acceptable". "Three times bigger" is not legally acceptable precisely because of that ambiguity. Many idioms are widely acceptable and contextually understandable, but you should never put them in a legal document because they carry ambiguity. Jan 13, 2015 at 22:02
• I'm saying that 'is acceptable' needs qualifying. If it leads to a dangerous misdosing say, it would surely be reckoned 'unacceptable'. And remember Murphy's Law for communication —anything that can be misunderstood will be misunderstood. I'd stick with 'is widely used'. Jan 13, 2015 at 23:16
• Swear words are widely used in 'communication'; they should not be labelled as 'acceptable' without further qualification. Context / register need specifying. Jan 14, 2015 at 11:52

To me the thing in saying "B is three times larger than A" (i.e., B= A+3A), when you MEAN "B is three times as large as A" (i.e., B=3×A") is WRONG, and this cannot be argued. Therefore, it should be discouraged in daily use and prohibited in printed material.

The argument that it's so common that it should be accepted, instead argues to me that we need a better education system, including more on logical thinking.

I believe the biggest culprit in this heresy is publishers, both in the media and in books, magazines, etc, who think "three times larger than" SOUNDS better than "three times as large as", and have few to no people with solid math/science backgrounds. A number of years ago I read somewhere that the editorial staff of most major newspapers has no one with a solid math/science background. Unverified, but it makes me wonder.

I should start by saying I'm not a mathematician!

"A is three times bigger than B"

I understand

A = B x 3.

So it seems very odd to me when the OP suggests that "if A is three times bigger than B then A is equal to B x 4".

On reflection I realise the OP is extrapolating - confusing unnecessarily - from a rare (arcane?) usage. It is much more usual ngrams to say

>"A is twice as big as B"

than it is to say

>A is "one time bigger" than B.