The Printable KISS Grammar Workbooks

da Vinci's
Study of
from Vitruvius's
De Architectura
The Logic of Subordinate Clauses


     Logic is a subject that has been studied by many different people, primarily philosophers and grammarians. All of these people have different ways of looking at logic, and, as a result, they use different words to describe what are essentially the same things. This can make the study of logic very confusing, but KISS attempts to simplify it by combining two specific perspectives -- the terms used by most traditional grammarians, and the terms of the philosopher David Hume.

     Hume claimed that thinking is primarily a matter of perceiving things and then establishing logical relationships among them. For Hume, there are three, and only three, basic logical relationships. They are "identity," "extension in time or space," and "cause/effect." Hume notes, however, a fourth possibility -- the three basic relationships can be combined in one or they can be compared

     KISS's grammatical perspective considers words or grammatical constructions (adjectives, adverbs, prepositional phrases, clauses, etc.) the same as "perceiving things." Having perceived, for example, a prepositional phrase, our task is then to interpret the logical relationship between that phrase and the word it modifies. Consider, for a more specific example, the four prepositional phrases in the following sentence:

{For six months} one {of the sailors} had been {on a long trip} {to South America}.

To understand the logic underlying these four phrases, we need to take them one at a time.
     Having identified "for six months" as a prepositional phrase, the first question we need to ask is "What does it modify?" We actually need to use logic to answer that question. We know that it is an adverbial phrase to "had been" because it tells "how long" they "had been." For Hume, this would be a logical relationship of "extension in time" (See, you have already been doing much of this.)
     The next phrase three phrases are fairly simple.  The first of these is "of the sailors." This phrase clearly chunks to "one," because it tells us what is meant by "one," or, in Hume's terms, it established the "identity" of the "one." "On a long trip" tells where they "had been." The word "where" refers to space, and in Hume's terms, this phrase expresses a logical relationship of "extension in space."
     The last phrase, "to South America," is more interesting, but still not very complicated. Our minds chunk constructions as efficiently as possible, so most people will see this phrase as modifying "trip." From that perspective, the phrase tells what kind of trip it was. In other words, it describes or identifies the trip. For Hume, this is a logical relationship of "identity." Other people, however, may see this phrase as modifying "had been." (Note that we can drop "on a long trip" from the sentence and still keep "to South America." -- "For six months one of the sailors had been to South America." But if we take out the word "trip," the "to South America" now chunks, as an adverb,  to "had been." It tells where he had been and thus functions, in Hume's terms, as "extension in space."

    As you work with grammar and Hume's logical relationships, you will soon find that in most sentences, the relationships are easy to see. You will also find many cases that can be explained in more than one way. You will, however, find a few cases that will really challenge your brain. But such challenges make your brain grow (literally, according to many neuroscientists). 

The Logic of Subordinate Clauses

Noun Clauses

     Since the primary function of nouns is to name things, we can consider noun clauses as fitting Hume's category of identity. Obviously,  nouns used as subjects identify what the meaningful subject of the clause is. In addition, of course, as with regular nouns, noun clauses that function as predicate nouns indicate an identity between the subject and the predicate noun:

That book is [what shewanted]. |

The questions that noun clauses answer are typically "who?" "whom?" and "what?". Thus the  most common subordinate conjunctions associated with noun clauses are "that, "what," "who," and "whom" but other conjunctions can also begin noun clauses, even if they identify a time, a space, cause, or effect:

Who knows[when theywill arrive]? |
[Where theywill go] is still uncertain. |
[Why theydid it] no one knows. |
He asked[how the computerworks]. |

Adjectival Clauses

      The function of adjectives is to describe, so adjectival clauses, like most noun clauses, convey what Hume would probably have considered to be the logical relationship of identity. In

The book [shewanted] is not{ in the library}. |

the subordinate clause identifies which book is meant. The questions that adjectives answer are usually "which?" "what?" and "what kind of?". The most common subordinate conjunctions used in adjectival clauses are "that," "who," and "which," but do not rely on the conjunctions to determine which type of clause you are dealing with. Adjectival clauses that modify words that denote times or spaces can be introduced by a wide range of conjunctions:

She remembered the time  [when shewas {in Pittsburgh}]. |
The airport [where theylanded] is very small. |

In other words, identify the type of clause by first determining how it functions in a sentence. Only then can you begin to explore its logical implications.

Adverbial Clauses

     From Hume's perspective, adverbial clauses are definitely the most interesting. Whereas nouns and adjectives relate primarily to Hume's first category (identity), adverbs primarily convey relationships of extension  and cause/effect.


      Whereas noun and adjectival clauses often identify times and places, adverbial clauses convey relationships between things in time and space. Note that the focus of these relationships is often reversible, that is, one can switch the clauses to put different ideas in the main clause S/V/C pattern. This is the pattern that everything chunks to, and thus the pattern that is the center of attention.

In Time

     To explore how adverbial clauses establish logical relationships, consider the following sentence:

The children were playing, | and their mother was fishing. |
The sentence establishes two facts, but it does not establish any relationship between them. It does not, for example, even state that the two actions were occurring at the same time. Compare it, for example, to the following:
a) The children were playing [while their motherwas fishing]. |
b) Their mother was fishing. [while the childrenwere playing]. |
The subordinating "while" in these two versions not only makes it clear that the two actions were occurring at the same time, it also changes the focus among the ideas. In the original compound sentence, the two main clauses were joined by "and" which joins equals, and thus the implication was that the two actions -- and their actors, were equally important. A subordinate conjunction, however, usually subordinates the idea in its clause, and thereby puts more emphasis on what is in the main clause. Thus, in (a), the focus is primarily on the children, whereas in (b) the mother is the center of attention.
     Whereas the focus can be changed with "while" simply by shifting the conjunction from one clause to the other, in many cases the shift requires the use of a different subordinating conjunction:
a) The children were playing [before their motherwas fishing]. |
b) Their mother was fishing. [after the childrenwere playing]. |
Subordination, and its effects of reversibility and focus, are important aspects of mature writing. Many third and fourth graders write almost exclusively using main clauses. As we grow older, we all teach ourselves how to use subordinate clauses, but some people gain greater control than others.
     Consider, for example, the writing of an essay. Even at the college level, many students have not mastered the idea of a thesis (the sentence that conveys the main idea of the essay) or topic sentences (sentences that state the main idea of a paragraph). In a good essay, the topic sentences support (and thus add to the focus on) the thesis. The sentences within a paragraph support (and thus add focus to) their respective topic sentences. In essence, a good essay presents a hierarchy of ideas, some more important than others. And this hierarchy extends down into the sentence level. At that level, subordinate conjunctions are a primary tool for establishing focus and conveying logical relationships among ideas. [For an example of this, see the MIMC exercise on "Alicia."]

In Space

     Reversibility and focus, discussed in relation to clauses of time, also apply to clauses of space (traditionally called clauses of "place"), so here we need simply look at an example.

He was fishing. | An accident happened. |
He was fishing [where an accidenthappened]. |
[Where hewas fishing], an accidenthappened.. |
Cause / Effect

     Based in Aristotelian philosophy, Hume's concept of cause and effect was much broader than what we normally consider today. It included, of course, the traditional concepts of clauses of cause, of result, and of purpose. But it also includes many of the other traditional subcategorizes of adverbial clauses. 

Clauses of Cause

      Some subordinate clauses state the cause of the idea expressed in the main clause:

Eddie went home [because his mothercalledhim (DO)]. |
[Since their regular teacherwassick (PA)], the classhad a substitute (DO). |
[As itwas gettinglate (PA)], the gamewas stopped early. |
"Because," "since," and "as" as the most frequently used conjunctions, but note that "since" can also be used to denote time, and "as" is also used both for time and for clauses of comparison.

     The grammarian Paul Roberts pointed out  that "that" clauses are frequently used to modify adjectives and that they can be considered as clauses of cause. He gives the example "I am sorry that you feel that way," and notes that "the clause that you feel that way states the cause of the sorrow." He gives additional examples:

We are so glad that you can come.
Perrydrip was indignant that no one liked his novel.
We were pleased that the roof was as tight as ever.
And he notes that "Often the conjunction is omitted: 'We are glad you can come'."
     He also notes that such clauses can also modify verbs, as in "I grieve that we shall never meet again." 

Clauses of Result (Effect)

     Some adverbial clauses express the result of the statement in the main S/V/C pattern. In most cases, the conjunction is "that," but it is usually preceded (and chunks to) either "so" or "such":

Sam wasso tired (PA) [that hefell asleep in class]. |
His teacher madesuch a fuss (DO) [that hewoke up]. |
Clauses of Purpose

     As their name suggests, adverbial clauses of purpose express the purpose (intended result) of the action that they modify. The most commonly used conjunctions are "so that," "so," "in order that," "that," and "lest."

Nancy studied hard [so that shewould get a good grade (DO)]. |
Marty and Sue arrived early [so theycould get a good seat (DO)]. |
[In order that theymight win], the teampracticed every day. |
[That theymight win], the teampracticed every day. |
Mom made a list (DO), [lest Dad should forget the bread (DO) and milk (DO)]. |
"Lest," of course, introduces a result that is to be avoided.

Clauses of Manner

     Clauses of manner answer the question "How?" How something is done affects what is done, and thus clauses of manner are, in the Aristotelian sense, cause/effect relationships. The typical conjunctions used are "as," "as if," "as though," and "in that."

Terrell runs[as hewalks -- with no apparent effort]. |
He looks[as if hehas seen a ghost (DO)]. |
In court, Jim acted[as though hewere in church]. |
Gerald failed[in that hedid not answermost (DO) of the questions]. |
Clauses of Condition

      As the name implies, clauses of condition state a required condition for the statement in the clause either to happen or to be believed. In other words, they state a necessary cause for the statement in the clause they modify.

a) [If itrains], the picnic will be canceled. |
b) They can drive to New York, [so long as the roads don't freeze]. |
c) [Unless heis mistaken], the Orioleswill win the World Series (DO). |
In (a), the "if" clause states a condition that would cause the picnic to be canceled. Similarly in (b), the "so long as" clause denotes a cause that would make the drive to New York dangerous. And in (c), the "unless" clauses states a condition that, if true, is a cause for not believing that the Orioles will win the World Series.

Clauses of Concession

     Clauses of Concession are a logical negation of clauses of condition. In concession, one concedes (agrees) that the expected result of a conditional clause did not, or may not, happen. The most common conjunctions are "although," "though," "even though," "while," and "whereas."

a) [Although itrained], the picnic was not canceled. |
b) They can drive to New York [even though the roads freeze]. |
Paul Roberts explained that " The clause of concession states something opposed to the main clause but does not deny the validity of the main clause. It is as if we should say: "I concede this (adverb clause) to be true; yet this (main clause) is true also." (Understanding Grammar, 327)
Comparisons (In Degree)

     The traditional category of adverbial clauses of degree is an example of fits Hume's fourth category. Identity, extension in time or space, and causes and effects can all be compared. Grammatically, this is usually expressed by a comparative adjective or adverbs such as "more," "less," or "as" followed by an adverbial clause that begins with "than" or "as."  "He is taller than she is" reflects a comparison of extension in space. "She is smarter than he is" reflects a comparison in degree of intelligence, a matter of identity.

Sally is more friendly (PA) [than Bobis]. |
Bob is less friendly (PA) [than Sallyis]. |
Note that in comparisons of degree the subordinate conjunction is usually "than," spelled with an "a," not an "e." Misspelling of "than" suggests that a person is not thinking about the logic behind what he or she is writing. When the things being compared are considered to be equal, the conjunction is usually "as," and the clause chunks to a preceding "as" in the sentence:
A Chevyisas good (PA) [as a Fordis]. |
Some prescriptive grammarians still object to the use of "like" as a subordinate conjunction, as in "No one sings like she does." But in view of the multiple meanings of "as" (comparison, time, and cause), "like" may be clearer in meaning since, as a subordinate conjunction, it is only used for comparison.