The Relative Pronouns "That" and "Which"

My opponent seems to be trying to shift the argument somewhat. He is now adding to the claim, saying "There are no such things as 'restrictive' and 'nonrestrictive' clauses." His original claim was just a little misguided, I can see where he might have been thinking of restrictive clauses when forming his resolution and accidentally made the resolution too general. But this new claim is down right incredible! No professional writer follows this new claim. He then goes on to mess with the examples, but remember he has no adequate justification for his comments about the examples (see item 3 below,) so they are nothing more than the restating of his claim. Let's pick apart his summary: (1) there is no intrinsic benefit (my opponent has yet to point one out)... Even his own sources point out the benefit of having restrictive and nonrestrictive clauses. Non restrictive clauses can be safely ignored when attempting to identify the object/subject under discussion. "The books in the library that Martha owns are moldy." has a different meaning than "The books in the library, which Martha owns, are moldy." The former implies that Martha only owns some of the books in the library and all of her books are moldy. The latter sentence implies that *all* of the books in the library are moldy and that Martha owns all of them. Even if we use "which" for the restrictive clause in the former sentence, the meanings are still different. (2) many professional writers and journalists make no such distinction... Is this claim true? We only have eight examples to go on. Some of the readers of this debate may know if this claim is true or false, but they certainly wouldn't know from any of the information presented in *this* debate. Is he talking here about the difference between restrictive and nonrestrictive clauses or only the difference between "that" vs "which"? Do any of his examples show "which" referring to a person as "that" can be? I think not. (3) most professional style guides and dictionaries make no such distinction... Answering this claim allows me to segue into my own summation... Let's look at all the professional style guides that have been sourced so far: * The OWL at Purdue * The Little Brown Handbook * The Chicago Manual of Style * The American Heritage Book of English Usage As I have already shown, *all* these guides, including the one sourced by Pro, agree with my position. "In the United States, most non-journalism writing follows the Chicago Manual of Style, while most newspapers base their style on the Associated Press Stylebook." (http://en.wikipedia.org...) To the list, I will add the AP Stylebook. It also makes the distinction between restrictive and nonrestrictive clauses (it calls them essential and nonessential clauses:) ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½"That" is the preferred pronoun to introduce essential clauses that ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½refer to an inanimate object or an animal without a name. "Which" is ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½the *only* acceptable pronoun to introduce a nonessential clause ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½that refers to an inanimate object or an animal without a name. ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½[stress added] There is no controversy, all of the professional style guides agree. Dictionaries, deal with word definition, not word usage (grammar,) and can be discounted as useful sources for the purposes of this debate. The only other source cited was Professor Brians' website. I sent an email to Professor Brians to ask him for more detail on the subject. He replied, "I generally like Michael Quinion's page on the subject: http://www.worldwidewords.org...; Something important to note here is that Michael Quinion "writes on international English from a British viewpoint." So what does he say on the subject: ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½... most modern grammar guides have caught up with the way people ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½actually use the language and now say that either relative pronoun ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½can be used with restrictive clauses. The key point to note in this quote from Mr. Quinion is that the style guides that have been sourced do not attempt to change current usage; rather they *reflect current usage*. More importantly, Mr. Quinion goes on to say: ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½One key proviso: though you can use which instead of that in ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½restrictive clauses, you can't do so the other way round: ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½non-restrictive clauses ought always to start with which. Once again, "that" and "which" are not *entirely interchangeable*. Even the source provided by Professor Brians agrees with my position. Voting for Con in this debate will mean that you agree with *every* authoritative source that has been cited.