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Subject:Re: That and Which--is it worth it? From:Jay Cherniak <CHERNJC1_at_TEAPOST -at- TEOMAIL -dot- JHUAPL -dot- EDU> Date:Fri, 16 Dec 1994 10:26:46 EST
I routinely edit that/which, as doing so was required in the federal
contractor laboratory where I worked for many years. Most of the time it
doesn't affect the meaning, but sometimes it does. I always recall an article
by William Safire on the problem. He gave an important example from the 1984
Republican national convention in which a subject of debate in the Republican
platform was, to the best of my recollection, the following sentence:
"We are opposed to any tax increase which would slow the rate of economic
This sentence is ambiguous because it lacks a comma before the word which.
The reader wonders whether the comma was mistakenly omitted. If it had a comma,
the sentence would mean that we are opposed to any tax increase, for any tax
increase would slow the rate of growth. Without the comma, it could mean we are
opposed only to those tax increases that would slow the rate of growth, but any
other increases would be fine.
The missing comma became a heated issue at the Republican convention, and
someone declared, "I will take that comma to the floor of Congress."
To avoid the ambiguity produced by the absence of a comma, use the word
that instead of which, so the sentence becomes, "We are opposed to any tax
increase that would slow the rate of economic growth," if that is what you
mean. If you mean it the other way, use which preceded by a comma.
I keep copies of the Safire article and give them to authors who ask me
about which/that. In effect, the rule says to either use (1) which, preceded by
a comma, or (2) that. Never use which without a comma.
As with all rules, there are exceptions. I once took a freelance copy
editing test for a publisher in San Francisco, and one of the rules on the
editorial style sheet was to use the word which without a comma if the
antecedent is preceded by the indefinite article. In other words, in the
sentence "I drive a 1964 Chevrolet which has a blue paint job," the word which
is perfectly acceptable without a comma because we already know what the
particular Chevy is that you drive, so we don't need the word "that" to
introduce a restrictive clause. I have tried explaining this to people over the
years, usually unsuccessfully. The distinction is subtle.
Applied Physics Laboratory
Johns Hopkins University
jay_cherniak -at- jhuapl -dot- edu
Text item: Text_1
I have a that/which question. I've had reputable sources tell me that
there are distinct rules for using "that" and "which"....namely, that
one is restrictive and the other is not. Here are the rules:
Restrictive: We purchased the software that provided all the necessary
features. (This sentence suggests that only one kind of software had
Non-restrictive: We purchased the software, which provided all the
necessary features. (This sentence suggests that there are lots of
kinds of software that could provide the features.)
Does anyone else out there follow this rule? It seems pretty subtle to
me. (If it changed the meaning of a sentence, I might worry about it,
but otherwise I would not.)