I'm Home, Lucid!

Last week we looked at some similar words that can be used interchangeably, and I shared my confusion with when to use “which” and when to use “that.” While compel and impel can be understood by differing definitions, and further and farther by different etymologies, which and that in the context of which (not that) I am referring is a matter of usage, not etymology or definition.

I even added parenthetical comments demonstrating some instances where it’s clear that “which” is the only word which (that?) can be used, and some instances where it’s clear that “that” is the only word which (that?) can be used. But I didn’t have space to clarify, so let’s get to that (an instance in which “which” won’t work) now.

What about which/that? You can see from my parenthetical comments above and last week that (can’t use “which” here) there are times when “which” and “that” can both make sense. But which (can’t use “that” here) word is the good word to use?

I found one site that suggests “use ‘that’ to introduce a ‘restrictive clause’ and ‘which’ to introduce a ‘nonrestrictive clause.’” The difference between a restrictive and a non-restrictive clause is explained as depending on whether you are referring to only the person or thing that you just mentioned (as I did with the site) or whether it describes not only what you’ve referenced but other things as well. Further, the site explains that if you remove the restrictive clause the meaning changes and the sentence loses specificity, but with an unrestrictive clause it wouldn’t.

Another site, while agreeing on the restrictive/nonrestrictive clause explanation, adds that usage has changed over the past century (as usage tends to do) and informs us that restrictive clauses are (or at least used to when grammar teaches could wield rulers on knuckles with impunity) not separated from the rest of the sentence with commas, while non-restrictive clauses are.  The article even quotes Sir Ernest Gowers, writing in the 1965 edition of Fowler’s Modern English Usage, saying he “comments rather sadly about this situation.” What is quoted is:

If writers would agree to regard that as the defining relative pronoun, and which as the non-defining, there would be much gain both in lucidity and in ease. Some there are who follow this principle now; but it would be idle to pretend that it is the practice either of most or of the best writers.

So, if you wish to be a stickler, use “that” when defining a word, and “which” when being less restrictive. 

Does that make it easy (or at least lucid)? If so, to misquote Ricky Ricardo, “I’m home, lucid!”

And that (not which), my friends, is a reference not readily understood by most people under age 50.