Less and Fewer
Less is used for mass nouns
Fewer is used for count nouns
Hmmmm...sounds like chemistry. So let's cook up this grammatical bomb a little more.
Fewer hairs: Less hair
Fewer is used when you can count the items. I can count the hairs on my chin, so I have fewer hairs, but actually I have more, more little bristles poking through on my chin. That's what happens after age 48, and it sucks, and it makes me feel like a bearded hag, which I guess I am, and I refuse to get it waxed because I just don't waste my time on such things. Now the hair on my head is different: the hair on my head, which is like a mane, is not countable. It's a mass of hair, not individual, countable bristles, like those stupid ones on my chin, so as I get older, I have less hair on my head because I have fewer countable individual hairs on my head. And, sadly, I have more hairs on my chin. Which I shave. So what. Get over it.
Less Aging: Fewer Lines
OK...now you are really confused...bad example. But let's stay with my appearance and the topic of my aging which obsesses me. I have more lines on my face. And are they countable? Yes, but it would take all day of obsessing in front of the mirror, and I am not that f@$ked-up about my appearance to count them, and what does that have to do with less and fewer anyway? Well, if I could stand in front of the mirror and bend time like Brad Pitt in that Button movie I would have fewer lines on my face with each passing moment. But that didn't work out so well for Brad.
Less humanity: Fewer people
Aging is all about less and fewer: more pounds of fat on your body, but that means less muscle. You can't count muscle, so you have less muscle mass, but I suppose that would mean you have fewer muscle fibers. Or do they shrink or what? You have less muscle tone. You can't count tone, so you have less tone. But you have fewer people admiring your legs as you walk down the street in shorts on a sunny afternoon when school is finally out and you can have a little fun for a change. I think it is this damn job that is making me old. I have less time to do the kind of fun things that keep me young. Like riding my white Arabian horse, galloping down the beach with his tail in the air, his nostrils flared...there is no one in sight and the world feels clean...Yes, less time for that sort of thing. Less time, fewer minutes, fewer hours, fewer days. But less time.
Less time: Fewer Days
And that's the essence, I suppose, to getting older...fewer minutes, fewer days. And the ones you have seem faster. The days, minutes, hours, rush by in a blur: two trains passing each other. Something is flashing by in the other direction, and it feels like my life, but I am going so fast, there is no way I can catch that other train, my past, my childhood, my children born and grown...it's racing away.
Less is more
So I guess there really is no less or fewer...now that i think about it, it's not chemistry, it's physics. Time is just melting down around me. Less fewer, mass count. Once I didn't know how to count, didn't know about less or fewer, and I had more.