When writers live together

Some people talk love in the bedroom. We speak grammar.

This was Rick's and my discussion this afternoon. I'd gone into read and he joined me.

RICK: They took out my Oxford commas. (He's talking about an article he'd sold and was published)

ME: You and I will never agree on Oxford commas.

RICK:  Hmmm

ME: A comma is shorthand for and. Thus when you use the Oxford comma it's like saying and-and. Deep down I don't see the need for it. (I love being on soap boxes)

ME: I have less books left to read than I want.

RICK: (After a long silence.) Fewer

ME:  What? (Laughing.

RICK:  Many people make a mistake all the time between fewer and less.

He got me. I wasn't sure of the difference. I reached for the Ipad. 

Merriman-Websters says fewer--a smaller number of persons or things.

The are wordier with less: 

" not so much : smaller in amount or number

The traditional view is that less applies to matters of degree, value, or amount and modifies collective nouns, mass nouns, or nouns denoting an abstract whole while fewer applies to matters of number and modifies plural nouns. Less has been used to modify plural nouns since the days of King Alfred and the usage, though roundly decried, appears to be increasing. Less is more likely than fewer to modify plural nouns when distances, sums of money, and a few fixed phrases are involved <less than 100 miles> <an investment of less than $2000> <in 25 words or less> and as likely as fewer to modify periods of time <in less (or fewer) than four hours>."

I read it to him. He replies hmmm. I think he's falling asleep. He's not.

RICK: Look up the difference between fewer and less.

Grammarmonster.com says.
Use less when referring to a single item.
Use fewer when referring to more than one item. 

The Oxford Dictionary says:

Use fewer if you’re referring to people or things in the plural (e.g. houses, newspapers, dogs, students, children).

Less is also used with numbers when they are on their own and with expressions of measurement or time.

I'm glad I learned something. 

I'm glad I live with another writer.