By Rudolf Schmid

Published as: Schmid, R. 1983. Which-hunting, or whatever happened to that? Taxon 32:621-622. Nov.

I see it in biology. I see it in history. I see it even in literature. Alas, what I tell you three times is true. The contagion is rampant. The satanic whiches are everywhere, usurping the grammatical world, whereas the thats are in severe decline.

One can hardly rejoice at the abysmal tendency to supplant totally "that" with "which" when they are used as relative pronouns in restrictive clauses. The grammatical distinction between the two relative pronouns has long been cherished. Although misusage of "which" for "that' is an old problem (for example, see the Victorian- and Edwardian-era quotations in Schmid, 1982), of late such misusage has become epidemic, as perusal of just about any journal reveals (for example, see below). And this misusage is common not only among non-English-speaking natives, who can be rightfully excused, but also even among English teachers and writers (e.g., Lee, 1969), who can only be stoutly condemned.

In the perhaps futile attempt to check this communicable which-disease, and because as a reviewer I am tired of noting on manuscripts "learn the proper distinction between 'that' and 'which,'" I offer some guidelines for their usage. While this information is readily available in English grammar books and in style manuals, the explanation in the generally unappreciated handbook by van Leunen (1978) is the clearest that [not "which"] I have seen. In contrast. the highly touted Follett (1966) and Fowler (1965) tend to be obscurantic in this regard. Much of the following explanation is admittedly culled from van Leunen's (1975) excellent account.

Here are some guidelines for the proper usage of "that" and "which" as relative pronouns in clauses. The examples in items "1" and "2" are from abstracts in the March 1983 Amer. J. Bot., which [not "that"], incidentally, exhibit four proper uses of "that", three proper uses of "which", and seven improper uses of "which".

(1) Read the sentence aloud. If the sentence with "which" sounds uncouth, usage of "that" is indicated. For example: "... have chloroplasts that [not "chloroplasts which"] lack starch." "A recording balance was achieved that [not "achieved which"] approximates...."

(2) Which-clauses are set off by commas, that-clauses are not. For example: "A complex wall encloses a central cavity that [not "cavity which"] may..." [but in another context proper might be "... the central cavity, which ..."]. And "... in the reduced megagametophyte of Plumbago zeylanica, which lacks synergids" [correct as quoted, but not with "zeylanica that"].

(3) "That" is used for restrictive clauses, that is, ones essential, defining. irremovable. In contrast, "which" is used for non-restrictive clauses, that is, ones parenthetical, descriptive, detachable. In many cases the sentence itself decides which relative pronoun to use. In some cases usage must be determined from context, that is. from the preceding sentence(s). As examples (from van Leunen, 1978), compare "the leaf that the grub has used for shelter now becomes its food" with "the leaf, which the grub has used for shelter, now becomes its food." In the first version "the leaf" is a fresh expression, one previously unmentioned or otherwise inadequate to indicate its real meaning; the clause is restrictive. In the second version "the leaf" was previously discussed, and so the reader need only be reminded about it; the clause is non-restrictive. See also the other examples above.

(4) Uprooting the clause and putting it after the main sentence may be helpful. If the uprooted clause makes sense in context, it is non-restrictive, and use of "which" with commas is indicated. However, if the uprooted version is nonsensical, the clause is restrictive, and use of "that" sans commas is indicated.

(5) "That" refers to persons or things. "which" usually to things. and "who" usually to persons.

(6) Play the odds. Use "that" without commas. This is the more common preferable construction (Fowler, 1965). Van Leunen (l978) rated its commonness as about ten to one. However, the preference "that"/"which" tally from the March 1983 Amer. J. Bot. given above is only eleven to three.

As a final note in this bewitching discussion, there is the usage of "that" in "than that" and similar constructions. For instance: "Apart from a cultural gap much wider than that that (not "that which") separates us from Bach and Handel, I think...." The previous guidelines still apply. Another possibility is to avoid the problem by using a gerund, that is, a verbal noun. Thus this example can be written: "Apart from a cultural gap much wider than that separating us from...."

In conclusion, to quote from Fowler (1965: 626), who is quotably seconded by Follett (1966: 323), there is "much gain both in lucidity and in ease" in using "that" as the restrictive, defining relative pronoun, and "which" as the non-restrictive, non-defining one.

Literature cited:

  • Follett, W. 1966. Modern American usage: A guide. Edited and completed by J. Barzun and collaborators. Hill & Wang, New York. [Also 1980 reprint by Avenel Books, New York.]
  • Fowler, H. W. 1965. A dictionary of modern English usage. 2nd ed. revised by E. Gowers. Oxford University Press, Oxford. [1st ed. = 1926.]
  • Lee, R. A. 1969. Orwell's fiction. University of Notre Dame Press, Notre Dame.
  • Schmid, R. 1982. The terminology and classification of steles: Historical perspective and the outlines of a system. Bot. Rev. 48: 817-93l.
  • van Leunen, M.-C. 1978. A handbook for scholars. Alfred A. Knopf, New York.

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