It’s one of the most common errors that you may hear while in conversation with someone. While both mean the same thing (namely indicating that something has a smaller value or is fewer in number than previously), it depends on the ‘something’ in question as to which of these two words you need to use.
Handily, if you’re already on top of mass nouns and how they’re different to count nouns, it’ll be super simple to figure this one out. If this is the first you’ve heard of ‘mass’ and ‘count’ nouns, then it’s probably a good idea to head here to get the full picture. For my regular readers, however, I’ll just quickly go over it again here.
A count noun is something you can naturally count, such as trees, cats, tables, doors and thousands of other things. Equally important, though, is that you can identify a single one of those things—you can easily identify a single door, for instance.
A mass noun, conversely, is something that cannot be counted, such as oxygen, grass, water, luck and dust. You cannot count a single one of these—ie, there is no such thing as a single luck or a single dust.
So why is knowing this important to the less vs fewer debate? Well, if you wanted to indicate that a mass noun has decreased in size, the word ‘less’ must be used. For example:
There is less sand on this beach than in a sandpit.
After the sale, there was less furniture to sell before the move.
Once her friend had split the load, there was less wood for Sarah to carry home.
The less time you waste here, the more you’ll have to yourself later.
You’d have less debt if you actually put your money into savings.
So while ‘less’ must be used for mass nouns, ‘fewer’ should be used with count nouns. For instance:
There were fewer rabbits at the pet shop today than yesterday.
Why are there fewer people on this train than normal?
At the park this morning, there were fewer people than there were dogs!
Is it just me or are there fewer books in this library than I have on my bookshelf at home?
The fewer members we have, the fewer phone calls we need to make to reschedule the meeting.
Once you’ve mastered the difference between mass and count nouns, therefore, you’ll have no problem discerning when to use ‘less’ and when to use ‘fewer’. The only downside of this knowledge is then realising how often people get it wrong in conversation, and then resisting the urge to correct them! Happy resisting.