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<strong>NEGATION</strong> <strong>AND</strong> <strong>GENERALIZED</strong> <strong>QUANTIFIERS</strong><br />

<strong>Frans</strong> <strong>Zwarts</strong><br />

Centre for Behavioural, Cognitive and Neuro-sciences<br />

Rijksuniversiteit Groningen<br />

1. Introduction<br />

Linguistic research has clearly shown that natural languages exhibit different forms of<br />

negation. Foremost among these are sentence negation and predicate negation. In this<br />

study, the relationship between both will be discussed. In particular, it wiu be argued<br />

that we can give an accurate description of the logical connections between sentence<br />

negation and predicate negation by reference to the semantical nature of the subject<br />

noun phrase. To this end, two important classes of generalized quantifiers will be<br />

distinguished, having to do with the familiar logical notions of consistency and<br />

completeness. Next, it will be shown that the distribution of negative adverbs in<br />

languages as Dutch and German forces us to make a distinction between predicate<br />

negation and verb negation as well. The logical relationship between these two forms<br />

of negation appears to be the same as that between sentence negation and predicate<br />

negation. Finally, it will be demonstrated that the difference between predicate negation<br />

and verb negation also shows up in languages such as English, particularly in co~ection<br />

with monotonicity patterns.<br />

2. Consistency<br />

It is well-known that there are considerable differences between sentential negation, an<br />

the one hand, and predicate negation, on the other. Less known is the fact that the<br />

logical relationship between both forms of negation depends entirely on the semantical<br />

nature of the subject. In order to convince ourselves, we do well to take the following<br />

two examples into consideration.<br />

(1) a At least two willows do not flower +<br />

It is not the case that at least two willows flower<br />

b Most weeping willows do not flower 4<br />

It is not the case that most weeping willows flower<br />

One sees immediately that the conditional in (la) can not be regarded as valid. For if<br />

the state of affairs is such that of the seven willows only four happen to flower, then the<br />

antecedent is true, but the consequent false. On the other hand, it is evident that the<br />

conditional in (lb) must be accepted as valid. If we are willing to accept the truth of the<br />

statement Most weeping willows do not flower, then we shall also have to acknowledge<br />

that it is not the case that the majority of weeping willows flowers. This entails that the<br />

quantifier which is associated with noun phrases of the form most N is invariably<br />

consistent in nature - consistent in the sense that it cannot contain a given set of


individuals as well as the complement of that set. For the sake of clarity we give the<br />

following definition.<br />

(2) Definition<br />

Let B be a Boolean algebra. A quantifier Q on B is said to be consistent iff<br />

for each element X of the algebra B: if -X E Q, then X # Q.<br />

Noun phrases which invariably receive a consistent quantifier as their semantic value,<br />

will accordingly be referred to as consistent noun phrases.<br />

The property of consistency can of course be formulated in more than one way. Indeed,<br />

it is readily established that the law of contraposition allows us to replace the definition<br />

in (2) by the alternative characterization in (3).<br />

(3) Definition<br />

Let B be a Boolean algebra. A quantifier Q on B is said to be consistent iff<br />

for each element X of the algebra B: if X E Q, then -X 4 Q.<br />

In spite of this equivalence, we prefer the definition in (2), primarily because it affords<br />

us a handy way of establishing the corollary below.<br />

(4) Corollary<br />

A noun phrase is consistent iff the following schema is logically valid:<br />

(1) NP (NEG VP) -, NEG (NP VP)<br />

This simple result is important, because it clearly shows that with a consistent noun<br />

phrase as subject the use of predicate negation invariably entails sentence negation.<br />

From the fact that the implication in (lb) is valid, it follows immediately that noun<br />

phrases of the form most N are consistent. Do not suppose that this exhausts the matter,<br />

for one easily proves that proper names and expressions of the forms both N, the n N,<br />

the NG and the N must also be regarded as belonging to the class of consistent noun<br />

phrases. In the &flowing examples, the use of predicate negation invariably entails<br />

sentence negation.<br />

(5) a Themistocles does not mourn<br />

It is not the case that Thernistocles mourns<br />

b Both feet are not ulcerated<br />

It is not the case that both feet are ulcerated<br />

c The seventeen donkeys do not bray<br />

It is not the case that the seventeen donkeys bray<br />

d The scientists do not drink coffee<br />

It is not the case that the scientist drink coffee<br />

e The shopkeeper does not waste time<br />

It is not the case that the shopkeeper wastes time


Similarly, one easily shows that expressions of the forms neither N, none of the n N and<br />

none of the N are also consistent in nature. To this end, it is enough to take the<br />

conditionals in (6) into consideration.<br />

(6) a None of the six donkeys does not bray<br />

It is not the case that none of the six donkeys brays<br />

b Neither foot is not ulcerated<br />

It is not the case that neither foot is ulcerated<br />

c None of the scientists does not waste time<br />

It is not the case that none of the scientists wastes time<br />

That each of these entailments is valid, follows from the definitions of the quantifiers<br />

corresponding to the noun phrases in question. To give an example, if none of the<br />

scientists does not waste time, then it follows that they all waste time, which in turn<br />

means that it is not the case that none of them wastes time. Consequently, the<br />

conditional in (6c) must be accepted as valid.<br />

The foregoing observations by no means imply that every noun phrase is consistent. The<br />

invalid implication in (1) clearly shows that expressions of the form at least n N do not<br />

belong to this class. In an analogous manner, one easily proves that noun phrases of the<br />

forms all N and no N can also not be regarded as consistent,, The next two examples,<br />

if interpreted as cases of regular negation, are both invalid.<br />

(7) a All students do not complain<br />

It is not the case that all students complain<br />

b No child does not complain<br />

It is not the case that no child complains<br />

By way of an illustration, it should be noted that, when the universe does not contain<br />

any child, the statements No child complains and No child does not complain are both<br />

true, which means that the denial It is not the case that no child complains must be<br />

regarded as false. Similarly, if the universe happens to lack students, the two statements<br />

All students complain and All students do not complain must both be accepted as true,<br />

and hence the denial It is not the case that all students complain must be rejected as<br />

false.<br />

In this connection, the behaviour of partitive noun phrases is rather interesting. It<br />

requires no lengthy reflection to see that expressions of the form at least n of the k N<br />

are consistent iff n > k/2. As a special case of the general pattern we have the valid<br />

conditional in (8).<br />

(8) At least three of the four children do not complain 3<br />

It is not the case that at least three of the four children complain<br />

On the other hand, if we consider expressions of the form (exactly) n of the k N, then<br />

the property of consistency appears to manifest itself just in case n f k/2. That is to say:<br />

(9) a Six of the eight children do not complain<br />

It is not the case that six of the eight children complain<br />

b One of the eight children does not complain


It is not the case that one of the eight children complains<br />

Finally, it should be easy to see that noun phrases of the form at most n of the k N are<br />

consistent only if n < k/2. In other words:<br />

(10) At most one of the four children does not complain +<br />

It is not the case that at most one of the four children complains<br />

The logical behaviour of partitive expressions thus appears to show some regularities.<br />

These find expression in three general laws concerning the phenomenon of consistency.<br />

(11)<br />

Laws of consistency for partitive' expressions<br />

(1) Expressions of the form at least n of the k N are consistent iff n > k/2.<br />

(2) Expressions of the form (exact&) n of the k N are consistent iff n # k/2.<br />

(3) Expressions of the form at most n of the k N are consistent iff n < k/2.<br />

We must therefore conclude that, with a substantial number of partitive subject phrases,<br />

the use of predicate negation implies sentence negation.<br />

With the aid of the foregoing test we can usually arrive at rather trustworthy judgments<br />

when it comes to deciding whether a given noun phrase does or does not enjoy the<br />

property of consistency. For the sake of clarity the outcomes of the test have been<br />

collected in table 1. The eighteen classes of noun phrases mentioned there must all be<br />

regarded as consistent. Such a catalogue, though at first sight merely of encyclopedic<br />

value, is important because we shall soon see that it leads to a coherent and complete<br />

account of the relationship between sentence negation and predicate negation.<br />

It should be pointed out in this connection that the property of consistency shows a<br />

striking resemblance to the logical theorem known as the law of contradiction. Indeed,<br />

the principle in question is meant to exclude the possibility that two contradictory<br />

propositions are both accepted as true. For that reason it is usually stated as '-(p A<br />

-p)'. One sees immediately that the property of consistency is similar to the logical<br />

theorem in that it excludes that two sets X and -X both belong to the quantifier. It will<br />

become apparent that this state of affairs has far-reaching consequences for our views<br />

on the different forms of negation.<br />

3. Completeness<br />

It requires no lengthy reflection to realize that the property of consistency has a<br />

counterpart. In order to convince ourselves, we take the following two examples into<br />

account.<br />

(12) a It is not the case that most tulips flower<br />

Most tulips do not flower<br />

b It is not the case that Seneca plays chess<br />

Seneca does not play chess


Table 1: Eighteen classes of consistent noun phrases.<br />

most N<br />

the majority of the N<br />

at least n of the k N (n > k/2)<br />

(exactly) n of the k N (n f k/2)<br />

at most n of the k N (n < k/2)<br />

both N<br />

the n N (n =. 0)<br />

the more than n N (n > 0)<br />

the no more than n N (n > 0)<br />

the Npl<br />

the Nsg<br />

neither N<br />

none of the n N (n > 0)<br />

none of the more than n N (n > 0)<br />

none of the no more than n N (n > 0)<br />

none of the N<br />

proper names<br />

negated proper names<br />

Clearly, the conditionaI in (124 cannot be regarded as valid. For if the state of affairs<br />

in the universe is such that half of all tulips flowers, then the antecedent is true, but the<br />

consequent false. On the other hand, the conditional sentence in (12b) surely belongs<br />

to the class of valid statements. If we accept the truth of the statement It zk not the case<br />

that Senecaplays chess, then we will also have to accept that Seneca does not play chess.<br />

Tbis entails that the quantifiers which are associated with proper names invariably are<br />

complete in nature - complete in the sense that it cannot be that neither the<br />

complement of a given set nor that set itself is a member of the quantifier in question.<br />

For the sake of accuracy we record this in the form of a definition.<br />

(1 3) Definition<br />

Let B be a Boolean algebra. A quantifier Q on B is said to be complete iff for<br />

each element X of the algebra B: if X & Q, then -X E Q.<br />

It is evident that the notion of completeness just introduced is the reversal of the notion<br />

of consistency mentioned before. This means that there are alternative characterizations<br />

of the property in question. Indeed, it is easily established that the law of contraposition<br />

allows us to replace the conditional in (13) by the equivalent statement 'if -X # Q, then<br />

X E Q'. Yet, we shall stick to the original definition, primarily because of the following<br />

corollary.<br />

(14) Corollary<br />

A noun phrase is complete if£ the following schema is logically valid:<br />

(1) NEG (NP VP) -* NP (NEG VP3<br />

This elementary result is important because it expresses in a lucid way that with a<br />

complete noun phrase as subject the use of sentence negation invariably implies<br />

predicate negation.<br />

From the fact that the implication in (12b) is valid, it follows immediately that proper<br />

names are complete. In an analogous way, one easily shows that negated proper names


are also complete in nature. This does not exhaust the stock, for a short search produces<br />

several other cases of completeness. The next two examples serve as an illustration.<br />

(15) a It is not the case that at least half of all tulips flowers -3<br />

At least half of all tulips does not flower<br />

b It is not the case that at most half of all cows has died<br />

At most half of all cows has not died<br />

There can be no doubt that both conditionals are valid. Indeed, if we accept the truth<br />

of the statement It is not the case that at least half of all tulips flowers, then we shall also<br />

have to accept that at least half of all tulips does not flower. Similarly, it is easily<br />

established that anyone who accepts the statement It is not the case that at most half of<br />

all cows has died as true will also be committed to the truth of At most half of all cows<br />

has not died. Consequently, we must conclude that noun phrases of the forms at least<br />

half of all N and at most half of all N both belong to the class of complete expressions.<br />

For the sake of clarity, these results have been collected in table 2. One sees<br />

immediately that two of the four classes of noun phrases mentioned are also consistent,<br />

namely proper names and their negations. This is important, because it follows from the<br />

relevant definitions that with a consistent and complete noun phrase as subject the use<br />

of sentence negation is equivalent to predicate negation. For that reason, the<br />

biconditional in (16) must be regarded as valid.<br />

(16)<br />

It is not the case that Themistocles mourns<br />

Themistocles does not mourn<br />

Indeed, it follows from the completeness of the expression Themistocles that the use of<br />

sentence negation entails predicate negation. Conversely, the consistent nature of the<br />

element in question guarantees that the use of predicate negation implies sentence<br />

negation. In this way, we can give a semantic explanation of the at first sight rather<br />

intricate relationship between both forms of negation.<br />

4. Sentence negation and predicate negation<br />

'I therefore hold it more suitable to regard negation as marking the content of apossible<br />

judgment." In this way, Frege expresses in the fourth paragraph of Begn~sschrifr his<br />

conviction that the different forms of negation must all be regarded as sentence<br />

negation. Of course, such a view entails that the use of predicate negation must also be<br />

reduced to sentence negation. In the posthumous fragment 'Logic', which dates from<br />

1897, he states this very clearly: 'In the German language we usually indicate that a<br />

thought is false by inserting the word 'not7 into the predicate.'2 To be sure, there are<br />

moments at which Frege expresses himself more carefully, as in the unpublished<br />

fragment 'Introduction to Logic' (1906), where we read:<br />

Frege (1980: 4).<br />

Frege (1979: 149).


-- -<br />

Table 2: Four classes of complete noun phrases.<br />

at least half of all N at most half of all N<br />

proper names negated proper names<br />

'To think is to grasp a thought. Once we have grasped a thought, we can recognize it as<br />

true (make a judgement) and give expression to our recognition of its truth (make an<br />

assertion). Assertoric force is to be dissociated fiom negation too. To each thought there<br />

corresponds an opposite, so that rejecting one of them is accepting the other. One can<br />

say that to make a judgment is to make a choice between opposites. Rejecting the one<br />

and accepting the other is one and the same act. Therefore there is no need of a special<br />

name, or special sign, for rejecting a thought. We may speak of the negation of a<br />

thought before we have made any distinction of parts within it. To argue whether<br />

negation belongs to the whole thought or to the predicative part is every bit as unfruitful<br />

as to argue whether a coat clothes a man who is already clothed or whether it belongs<br />

together with the rest of his clothing. Since a coat covers a man who is already clothed,<br />

it automatically becomes part and parcel with the rest of his apparel. We may,<br />

metaphorically speaking, regard the predicative component of a thought as a covering<br />

for the subject-component. If further coverings are added, these automatically become<br />

one with those already there."<br />

But that does not alter the fact that Sommers is absolutely right when he claims that<br />

Frege's way of portraying the matter rests on 'the negatability criterion for genuine<br />

subjecthood'? According to this criterion, the status of logical subject can only be<br />

assigned to a given phrase if attachment of two contradictory predicates to the<br />

expression in question will give us two contradictory propositions. In other words, should<br />

we wish to speak of a logical subject, then the use of predicate negation must in Frege's<br />

opinion invariably be equivalent to sentence negation. It is evident that such a<br />

requirement entails that proper names be assigned a separate place, for on the basis of<br />

the fact that Aristotle is not a philosopher is the denial of Aristotle is a philosopher, Frege<br />

labels the occurrence of Aristotle in both sentences as the logical subject. On the other<br />

hand, he refuses to regard the occurrence of all mammals in All mammals we land-<br />

dwellers as the logical subject, because the statement All mammals are not land-dwellers<br />

clearly cannot be classified as the denial of All mammals are land-dwellers. Indeed, his<br />

remarks in 'On Concept and Object' show that Frege is not even willing to analyze the<br />

expression all marnmak as a logical unit3 In this way, he withholds logical<br />

Frege (1979: 185).<br />

Sommers (1982: 27).<br />

Frege (1980: 47-48) offers us the following explanation: 'We may say in brief, taking 'subject and<br />

'predicate' in the linguistic sense: A concept is the reference of a predicate; an object is something that<br />

can never be the whole reference of a predicate, but can be the reference of a subject. It must here be<br />

remarked that the words 'all', 'any', 'no', 'some', are prefixed to concept-words. In universal and particular<br />

affirmative and negative sentences, we are expressing relations between concepts: we use these words to<br />

indicate the special kind of relation. They are thus, logically speaking, not to be more closely associated


constituenthood from phrases that grammar considers to be unsuspected units, and<br />

creates an unbridgeable gap between logical form, on the one hand, and grammatical<br />

form, on the other. Whether Frege was really content with this solution is not clear, for<br />

at the end of the posthumous fragment 'Logic' he concludes that the use of the word not<br />

'in ordinary language is a purely external criterion and an unreliable one at that7, and<br />

complains about the fact that 'we are tangling with some thorny problems hereY.'<br />

The difficulties that Frege experiences can be attributed to the fact that he sticks to a<br />

first order analysis of sentences. If we give up this restriction and regard noun phrases<br />

as second order expressions, then any doubt a. to the relationship between sentence<br />

negation and predicate negation must disappear. For it can be described completely in<br />

terms of the earlier mentioned properties of consistency and completeness. To forestall<br />

any misunderstandings, we do well to express this in the form of two general laws<br />

concerning the use of both forms of negation.<br />

(17)<br />

Laws of negation (preliminary version)<br />

(1) The use of sentence negation implies predicate negation just in case the<br />

subject of the sentence is complete in nature.<br />

(2) The use of predicate negation implies sentence negation just in case the<br />

subject of the sentence is consistent in nature.<br />

It goess without saying that, in the presence of a subject which is complete and<br />

consistent, the use of sentence negation is equivalent to predicate negation.<br />

4. The theory of quaternality<br />

There are other formulations of the laws of negation which are perhaps less obvious, but<br />

completely equivalent to the original formulations. To this end, we shall introduce three<br />

operations which, applied to given quantifiers, produce new quantifiers. Starting from<br />

a quantifier Q on a Boolean algebra B, the first enables us to form the complement of<br />

Q, that is to say, the quantifier consisting of all elements of the algebra B which do not<br />

belong to Q. This new quantifier will be written as -Q. With the aid of the second<br />

operation we form the so-called contradual of Q, represented by the symbol -Q. This<br />

is the quantifier which consists of all elements X of the algebra B such that -X E Q. The<br />

third operation, finally, serves to create a new quantifier -Q- which we call the dual of<br />

with the concept-words that follow them, but are to be related to the sentence as a whole. It is easy to<br />

see this in the case of negation. If in the sentence<br />

'all mammals are land-dwellers'<br />

the phrase 'all mammals' expressed the logical subject of the predicate are land-dwellers, then in order<br />

to negate the whole sentence we should have to negate the predicate: 'are not land-dwellers'. Instead, we<br />

must put the 'not' in front of 'all'; from which it follows that 'all' logically belongs with the predicate.' The<br />

reader should note that Frege (1979: 87-117) contains a preliminary draft of the article.<br />

' Frege (1979: 150).


Q. It contains each element X of the algebra B such that -X $ Q. For the sake of<br />

transparency we record this in the form of a definition.'<br />

(18) Definition<br />

Let B be a Boolean algebra and let Q be a quantifier on B. Then:<br />

(1) The complement of Q is the quantifier -Q = {X E B: X 4 Q).<br />

(2) The contradual of Q is the quantifier Q- = {X E B: -X E Q).<br />

(3) The dual of Q is the quantifier -Q- = {X E B: -X 4 Q).<br />

One sees immediately that it makes no difference whether we regard the dual -Q- as the<br />

complement of the contradual of Q or as the contradual of the complement of Q. For<br />

this reason we write -Q- instead of -(Q-) or (-Q)-. It is also readily established that the<br />

complement of the complement of Q, the contradual of the contradual of Q, and the<br />

dual of the dual of Q are all identical to Q. In symbols: --Q = Q-- = --Q--= Q.<br />

Likewise, one easily shows that the contradual of the dud of Q is equal to the<br />

complement of Q, and that the complement of the dual of Q is equal to the contradual<br />

of Q. That is to say: -Q-- = -Q and --Q- = Q-.<br />

duals +<br />

complements<br />

-Q-<br />

Figure 1<br />

contraduals<br />

contraduals<br />

complements<br />

-, duals<br />

With the aid of these equations, we can visualize the mutual relationships between Q, -<br />

Q, Q- and -Q- by means of the picture in figure 1. The square represented there shows<br />

a clear resemblance with the traditional square of opposition.2 As an illustration of this<br />

The model-theoretic notion of the dual of a quantifier is discussed in Barwise and Cooper (1981:<br />

197). Among other things, they call attention to the important subclass of self-dual quantifiers, defined<br />

by the equation Q = -Q-.<br />

Gottschalk (1953) points out that every involution in a logical or mathematical system gives rise<br />

to a theory of quaternality and that the square of quaternality, of which the classical squares of opposition<br />

are special cases, provides a diagrammatic representation for much of this theory.<br />

45 1


correspondence, we consider the noun phrases all weasels (Q), not all weasels (-Q), no<br />

weasel (Q-), and at least one weasel (-Q-). By reference to the square it is readily<br />

established that all weasels and at least one weasel are each other's duals, just as not all<br />

weasels and no weasel are. Similarly, we can show that not all weasels is the contradual<br />

of at least one weasel and that no weasel is the contradual of all weasels. The expressions<br />

at least one weasel and no weasel, finally, must be regarded as each other's complements.<br />

Indeed, it requires no lengthy reflection to realize that every noun phrase determines a<br />

square of opposition. For this reason we are entitled to say that an expression as neither<br />

ox is the contradual of both oxen.<br />

The significance of such squares of opposition lies in the fact that they enable us to give<br />

an alternative characterization of the properties of consistency and completeness. The<br />

next two lemmata provide the necessary details.<br />

(19) Lemma<br />

(20) Lemma<br />

Let B be a Boolean algebra. The following two statements about a quantifier<br />

Q on B are equivalent:<br />

(1) Q is consistent.<br />

(2) Q c -Q-.<br />

Proof. Suppose that Q is consistent and that X E Q. Then -X # Q, and so, by<br />

the definition of duality, X E -Q-. Hence, Q c -Q-. Conversely, if Q c -Q- and<br />

X E Q, then X E -Q-. SO, by the definition of duality, -X # Q. II<br />

Let B be a Boolean algebra. The following two statements about a quantifier<br />

Q on B are equivalent:<br />

(1) Q is complete.<br />

(2) -Q- r Q.<br />

Proof. Suppose that Q is complete and that X E -Q-. Then -X # Q, by the<br />

definition of duality, and so X G Q, by the completeness of Q. Hence, -Q- r<br />

Q. Conversely, if X # Q, then X # -Q-, because of (2), and so, by the definition<br />

of duality, -X E Q. II<br />

From this it follows that a quantifier which is both consistent and complete is self-dual.<br />

That is to say:<br />

(21) Corollary<br />

Let B be a Boolean algebra. The following two statements about a quantifier<br />

Q on B are equivalent:<br />

(1) Q is consistent and complete.<br />

(2) Q = -Q-.<br />

The above result provides us with two tests. For it is easily established that quantifiers<br />

which are consistent and complete have the property that -X belongs to Q iff X does not<br />

belong to Q. But from the fact that Q is self-dual in such cases we may also infer that


X belongs to Q iff -X does not belong to Q. As a consequence, we have the following<br />

corollary:<br />

(22) Corollary<br />

A noun phrase is consistent and complete iff the following schemata are<br />

logically valid:<br />

(1) NEG (NP VP) - NP (NEG VP)<br />

(2) NP VP NEG (NP (NEG VP))<br />

That proper names, regarded as consistent and complete noun phrases, satisfy the first<br />

requirement has already been established by means of the valid equivalence in (16).<br />

That they also satisfy the second requirement is shown by the validity of the<br />

biconditional in (23).<br />

(23) Themistocles mourns +<br />

It is not the case that Themistocles does not mourn<br />

Consequently, we may conclude that proper names belong to the class of expressions<br />

which are self-dual.<br />

In view of these findings, the earlier formulations of the laws of negation may be given<br />

a different form. Instead of saying that in the presence of a consistent subject the use<br />

of predicate negation implies sentence negation, it is possible to say that the subject<br />

should be contained in its dual if the use of predicate negation is to imply sentence<br />

negation. Conversely, it is necessary that the subject contains its dual if the use of<br />

sentence negation is to imply predicate negation. This is expressed in the following law<br />

concerning equivalent forms of negation.<br />

(24) Equivalent forms of negation<br />

The use of sentence negation is equivalent to predicate negation just in case<br />

the subject is consistent and complete, that is to say, just in case the subject<br />

is self-dual.<br />

It will be shown that this rather surprising relationship between negation and duality is<br />

significant in other respects as well.<br />

5. Laws of negation<br />

With the aid of the theory of quaternality, we can establish a number of simple facts<br />

concerning the mutual relationships between Q, -Q, Q- and -Q-.<br />

(25) Theorem<br />

Let B be a Boolean algebra. The following statements about a quantifier Q on<br />

B are equivalent:<br />

(1) X # Q.


The importance of this elementary result lies in the fact that it enables us to provide<br />

several alternative characterizations of the use of sentence negation. The next corollary<br />

gives the relevant details. It should be emphasized that we write NpN for the<br />

complement of a noun phrase, NP' for the contradual of a noun phrase, and N P for ~<br />

the dual of a noun phrase.<br />

(26) Laws of negation I<br />

The following schemata are logically equivalent:<br />

(1) NEG (NP VP)<br />

(2) N P (NEG ~ VP)<br />

(3) NPN W<br />

(4) NEG (NP' (NEG W))<br />

It should be obvious that, in the presence of a self-dual subject, the use of sentence<br />

negation is equivalent to predicate negation. If there is no such subject, the transition<br />

from sentence negation to predicate negation or from predicate negation to sentence<br />

negation must involve the replacement of the subject by its dual. As a special case of<br />

this general law, we have the logical equivalence of It is not the case that every cow moos,<br />

At least one cow doesn't moo, Not every cow moos, and It is not the case that no cow<br />

doesn't moo.<br />

Do not suppose that this exhausts the matter, for the square of opposition depicted in<br />

figure 1 also permits us to derive the logical equivalences in (27) - (29).<br />

(27) Laws of negation I1<br />

The following schemata are logically equivalent:<br />

(1) NEG (NPD VP)<br />

(2) NPpG VP)<br />

(3) NP VP<br />

(4) NEG ( NP~ (NEG VP))<br />

(28) Laws of negation 111<br />

The following schemata are logically equivalent:<br />

(1) NEG (NPC VP)<br />

(2) N P (NEG ~ VP)<br />

(3) NPD VP<br />

(4) NEG (NP (NEG VP))<br />

(29) Laws of negation TV<br />

The following schemata are logically equivalent:<br />

(1) NEG (NP~ VP)<br />

(2) N P (NEG ~ W)


(3) NP VP<br />

(4) NEG (NP~ (NEG VP))<br />

As an illustration of these laws, it is sufficient to observe that the proposition It is not<br />

the case that at least one cow moos is equivalent to Every cow doesn 't moo, No cow moos<br />

and It is not the case that not every cow doesn't moo by the four schemata in (27). This<br />

is important because it shows clearly that a sentence can be denied in several ways. The<br />

idea of a one-to-one correspondence between positive and negative sentences, once<br />

suggested by Kraak (1966: 81), must therefore be immediately discarded.<br />

5. Verb negation<br />

Thus far, we have assumed that there are only two types of negation - sentence negation<br />

and predicate negation. As should be evident to anyone who is familiar with the word<br />

order of Dutch and German subordinate clauses, there exists a third type as well - to<br />

wit, verb negation1 By way of an example, consider the Dutch sentence in (30).<br />

(30)<br />

Ik weet dat hij veel opgaven niet begrijpt.<br />

I know that he many problems not understands<br />

'I know that there are many problems which he doesn't understand.'<br />

Clearly, the scope of the negative adverb niet 'not' is the transitive verb begnypt<br />

'understands' alone. This contrasts sharply with the example in (31), where the scope of<br />

niet is either the direct object veel opgaven 'many problems' or the entire verb phrase<br />

veel opgaven begrijpt.<br />

(31)<br />

Ik weet dat hij niet veel opgaven begrijpt.<br />

I know that he not many problems understands<br />

'I know that he doesn't understand many problems.'<br />

At first sight, the possibility of verb negation seems to be restricted to languages such<br />

as Dutch and German. However, when one takes the distribution of some and any into<br />

consideration, it becomes clear that English has this type of negation as well. The next<br />

two conditionals may serve as an illustration.<br />

(32) John didn't see any of the paintings .-,<br />

John didn't see any of the modern paintings<br />

(33)<br />

John didn't see some of the modem paintings<br />

John didn't see some of the paintings<br />

The validity of the entailment in (32) shows that the object noun phrase is the argument<br />

' of a monotone decreasing function. This is not the case in (33), where the direction of<br />

the conditional inference is in fact the opposite of what we saw before. In other words,<br />

Brown (1991) argues that the Scots spoken in Hawick also exhibits verb negation. One of his<br />

examples is He's still no working ('It is the case that he is still out of work'), where the position of the<br />

negative after the adverb still unambiguously indicates that the scope is the main verb.


the object noun phrase in (33) must be the argument of a monotone increasing function.<br />

In what follows, we will show that this can be explained if we assume that the<br />

occurrence of some of the modem paintings in (33) is the argument of the negative<br />

transitive verb phrase didn't see. Before we address this matter in more detail, we do<br />

well to establish some simple facts concerning the logical relationship between predicate<br />

negation and verb negation.<br />

By means of the theory of quaternality, we can provide several alternative ways of<br />

characterizing predicate negation. To show this, we assume (1) that extensional transitive<br />

verbs are of type (e, (e, t)), being associated with two-place relations between<br />

individuals; (2) that object noun phrases, like subject noun phrases, are generalized<br />

quantifiers of type ((e, t), t); and (3) that the combination of an extensional transitive<br />

verb with denotation R and an object noun phrase with denotation Q is to be<br />

interpreted as the set {a E U: {b E U: R(a,b)) E Q), where U is the universe of<br />

discourse.' In terms of these principles and the result established in (25), we can prove<br />

that the set {a E U: {b E U: R(a,b)) + Q), which corresponds to predicates of the form<br />

NEG (V NP), is identical to the sets {a E U: {b E U: R(a,b)) E -Q-), {a E U: {b E U:<br />

R(a,b)) E -Q), and {a E U: {b E U: R(a,b)) 4 Q-). The following lemma, which is an<br />

obvious extension of the result obtained in (26), gives the necessary linguistic details.<br />

For the sake of transparency, we present two versions - one for SVO-languages, the<br />

other for SOV-languages.<br />

(34) Laws of negation V<br />

The following schemata are logically equivalent:<br />

S VO- languages SOV-languages<br />

(1) NP (NEG (V (1) NP (NP V))<br />

(2) NP ((NEG V) NP (2) NP (NP (NEG V))<br />

(3) NP (v NP*) (3) NP (NP~ V)<br />

(4) NP (NEG ((NEG V) NP~)) (4) NP (NEG (NP~ (NEG v)))<br />

It should be clear that, in the presence of a simple transitive verb and a self-dual object,<br />

the use of predicate negation is equivalent to verb negation. If there is no such object,<br />

the transition from predicate negation to verb negation or from verb negation to<br />

predicate negation must involve the replacement of the object by its dual. As a special<br />

case of this general law, we have the logical equivalence of John (didn't (solve every<br />

problem)) and John ((didn't solve) some problem (s)) .<br />

Van Benthem (1986) seems to have been one of the first to propose such a treatment. In defense<br />

of this approach, he points out that extensional transitive verbs are sensitive to the semantic structure of<br />

the object noun phrase. If the expression in question is monotone decreasing, as in John ate or drank<br />

nothing, we may legitimately pass to John ate nothing or John &mk nothing. On the other hand, if the<br />

object is monotone increasing, as in John heard and felt something, we may legitimately pass to John<br />

heard something or John felt something. A more elaborate discussion of this matter can be found in<br />

Hoeksema (1989, 1991a, 1991b) and van Benthem (1991). Keenan (1989) proposes a slightly different<br />

treatment of subject and object noun phrases, based on what he refers to as semantic case. His approach<br />

is adopted by <strong>Zwarts</strong> (1991), in connection with a unified treatment of reflexives and noun phrases.


This does not exhaust the matter, for the theory of quaternality also permits US to derive<br />

the lemmata in (35) - (37).<br />

(35) Laws of negation VI<br />

The following schemata are logically equivalent:<br />

S VO-languages SO V- languages<br />

(1) NP (NEG (V wD)) (1) NP (NEG (NP~ V))<br />

(2) NP ((NEG V) NP) (2) NP (NPJrnG V))<br />

(3) NP (v NP~) (3) Np (Np V)<br />

(4) NP (NEG ((NEG V) NP~)) (4) NP (NEG ( NP~ (NEG v))<br />

(36) Laws of negation VII<br />

The following schemata are logically equivalent:<br />

v))<br />

(1) NP (NEG (V NP'A) (1) Np PC<br />

(2) Np ((NEGDV) Np 1 (2) Np (5 (NEG V))<br />

(3) NP (V NP ) (3) NP (Np v)<br />

(4) NP (NEG ((NEG V) NP)) (4) NP (NEG (NP (NEG V))<br />

(37) Laws of negation VIII<br />

The following schemata are logically equivalent:<br />

SVO-languages S 0 V- languages<br />

(1) NP (NEG (V NP~J) (1) NP (NEG ( NF~ v))<br />

(2) NP ((NEG V) NP ) (2) NP (NPc (NEG V))<br />

(3) NP (V NP) (3) NP (NP V)<br />

(4) NP (NEG ((NEG V) NP~)) (4) NP (NEG (NP* (NEG V))<br />

As an illustration of these laws, it is sufficient to observe that the English proposition<br />

John (didn't (solve any of the problems)) is equivalent to John ((didn't solve) all of the<br />

problems) and John (solved none of the problems) by the SVO-schemata (I), (2) and (3)<br />

in (35).' The SOV-patterns can be exemplified by means of the logically equivalent<br />

Dutch propositions Ik weet dat zzj' (niet (alle opgaven heeft opgelostt)) 'I know that she<br />

(didn't (solve all of the problems))', Ik weet dat zij (mixstem 6dn opgnve (niet heeft<br />

opgelost)) 'I know that she ((didn't solve) some of the problems)', ik weet dat zij ((niet<br />

It is much more dicult to find an instance of the fourth schema in (351, due to the absence of<br />

sentences with more than one preverbal negation in standard E~ghsh. Brown (1991: 82, 84, 85) reports<br />

cases involving two or even three negations in Hawick Scots, among them He couldnae have been no<br />

working 'It is impossible that he has been out of work', He could no have been no working 'It is possible<br />

that he has not been out of work', and He couldnae have no been no working 'It is impossible that he<br />

has not been out of work'.


Figure 2<br />

PUF, > u~~<br />

alle opgaven) heeff opgelost 'I know that she (solved not all of the problems)', and Ik weet<br />

dat zij (niet (geen enkele opgave (niet heeft opgelost))). It should be clear that the<br />

schemata in (26) - (29), on the one hand, and those in (34) - (37), on the other, can be<br />

combined in various ways. The proposition It is not the case that everyone solved some<br />

of the problems, for example, is equivalent to Someone (didn't (solve some of the<br />

problems)) and Someone ((didn't solve) all of the problems) by the schemata (1) and (2)<br />

in (26) and (34).<br />

6. The semantics of extensional transitive verbs<br />

In their Boolean Semantics for Natural Language (1985), Keenan and Faltz describe a<br />

way of endowing extensional verbs and verb phrases with a third-order Boolean<br />

structure. The approach advocated there contrasts in interesting ways with the first-<br />

order treatment of the same expressions in Keenan (1989). In this section, their<br />

proposals are summarized and related to the analysis presented in Partee and Rooth<br />

(1983).<br />

For Keenan and Faltz, as for many others, generalized quantifiers are sets of sets of<br />

individuals, belonging to what is commonly referred to as the universe of NP<br />

denotations, written UNP. The Boolean operations in this type are of course union,<br />

intersection and complementation. Keenan and Faltz give a special status to NP<br />

denotations corresponding to individuals. If the individual i is an element of the universe<br />

U, the corresponding quantifier is the set {X c U: i E U}, known as the principal<br />

ultrafilter generated by i. The set {PUF(i): i E U) of principal ultrafilters corresponding<br />

to individuals is denoted PUFU.


As Partee and Rooth (1983) show, PUF has a useful property: it is a set of so-called<br />

free generators for the Boolean algebra &.' This means that each element of UNp can<br />

be represented as a Boolean combination of elements of PUFu and that any function<br />

g from Uw to an arbitrary Boolean algebra B can be extended uniquely to a<br />

homomorphism h from UNp to B. Pictorially, the situation can be represented as in<br />

figure 2, where i is the inclusion map of PUFu into UNP.<br />

Following in essence Partee and Rooth (1983), we can now describe the higer-order<br />

Boolean structure that Keenan and Faltz assign to the space of extensional transitive<br />

verbs and verb phrases, which they take to be Ho%(UW Uv), :he s;t of Boolean<br />

homomorphisms from U to the algebra Uvp = 2 . First, a ijec ion etween Horn<br />

(Urn, Uw) and uVU rasserted to exist. Then this bijection is used to transfer the<br />

Boolean structure whch uVpU has as an algebra of sets to Horn (Urn, U,). Let f be<br />

a function from U to Uw and let I be the function which maps each element of U to<br />

the corresponding principal ultrafilter. Because PUFU is a set of free generators for the<br />

Boolean algebra Urn, f o I-' extends uniquely to a homomorphism h: Um + UVP.<br />

Consequently, we can define a map M: Uw U<br />

+ Horn (%, UW) which carries f to<br />

the corresponding homomorphism h. This can be depicted as in figure 3.<br />

PUF,<br />

Figure 3<br />

i<br />

M is a function, because the extension of M is unique. M is an injection one-to-one),<br />

because if fi # % f1 0 I-' f f2 0 I-', and M(fi) and M(fi) extend fi 0 I and f2 0 I-<br />

l, respectively. Finally, M is a surjection (onto), because if k is in Horn (Urn, UVP), M(1<br />

i o k) = k, again because the extension is unique. Thus, M is a bijection between<br />

uWU and Horn (Urn, UVP).<br />

M can be used to define Boolean operations on Horn (UNP, UVP). That is to say:<br />

The notion of a free generator is discussed extensively in Sikorski (1969: 42-45) and Halmos (1963;<br />

4-46).<br />

\


(38) Definition<br />

It is easily established that Horn (UW, U*), with operations so defined, is a Boolean<br />

algebra. In practice, what this means IS that the result of applying negation, regarded as<br />

the operation of Boolean complementation, to a transitive verb is another transitive verb<br />

with the same homomorphic properties as the original one. Thus, an expression such as<br />

didn't see, analyzed as a negative transitive verb phrase, denotes a homomorphic, hence<br />

monotone increasing, function.<br />

7. Monotonicity analyses<br />

By means of the semantics just described, we can associate a sentence such as John<br />

didn't see some of the paintings with the categorial derivation in (39). It is easy to see<br />

that application of didn't to see gives us the monotone increasing (more precisely,<br />

homomorphic) transitive verb phrase didn't see. The next step in the derivation uses the<br />

operation of function composition to create the expression John didn't see.<br />

(39) John didn't see some of the paintings<br />

S/VP ((VP/NP)/(VP/NP)) VP/NP NP<br />

f G ?<br />

It should be clear that the noun phrase some of the paintings is the argument of a<br />

monotone increasing function - to wit, the Boolean homomorphism associated with the<br />

composite function John didn't see. This explains the validity of the conditional in (33).<br />

To understand the relationship between monotonicity properties and function<br />

composition, one does well to take the table in figure 4 into consideration.<br />

Figure 4


As an illustration of this monotonicity table, consider the categorial derivation in (40).<br />

Clearly, the negative transitive verb phrase didn't see is the result of composing the<br />

monotone decreasing function didn't and the monotone increasing function see.<br />

According to the table, this derived expression is monotone decreasing in nature. In a<br />

similar way, we can use composition to create the phrase John didn't see, which must<br />

also be regarded as a monotone decreasing expression.<br />

John didn't see some of the paintings<br />

VP/NP NP<br />

+ J, +<br />

It should now be clear that the expression some of the paintings in (40) occurs in a<br />

downward monotonic context. Hence, the validity of the conditional in (32). This brings<br />

our discussion of the relationship between various types of negation to an end.<br />

References<br />

Banvise, J. and R. Cooper (1981), 'Generalized Quantifiers and Natural Language.'<br />

Linguistics and Philosophy 4: '159-219.<br />

van Benthem, J. (1986). Essays in Logical Semantics. Dordrecht: Reidel.<br />

van Benthem, J. (1991). Language in Action: Categories, Lambdas and Dynamic Logic.<br />

Amsterdam: North-Holland.<br />

Brown, K. (1991). 'Double Modals in Hawick Scots.' In: P. Trudgill and J.K. Chambers<br />

(eds.) Dialects of English. London: Longman, 74-103.<br />

Frege, G. (1979). Posthumous Writings. Edited by H. Hermes, F. Karnbartel, and F.<br />

Kaulbach, with the assistance of G. Gabriel and W. Rodding. Translated by I?. Long<br />

and R. White, with the assistance of R. Hargreaves. Oxford: Basil Blackwell.<br />

Frege, G. (1980). Translations from the Philisophical Wn'tings of Gottlob Frege. Edited by<br />

P. Geach and M. Black. Index prepared by E.D. Klernke. Third edition. Oxford:<br />

Basil Blackwell.<br />

Gottschalk, W.H. (1953). 'The Theory of Quaternality.' The Journal of Symbolic Logic<br />

18: 193-196.<br />

Halmos, P.R. (1963). Lectures on Boolean Algebras. Princeton, New Jersey: Van<br />

Nostrand.<br />

Hoeksema, J. (1989). A Categorial Theory of Reanalysis Phenomena. Unpublished<br />

manuscript, University of Pennsylvania.<br />

Hoeksema, J. (1991a). 'Algemene Kwantoren en de Small Clause Kwestie.' In: TABU:<br />

Bulletin voor Taalwetenschap 21, 77-85.<br />

Hoeksema, J. (199lb). 'Complex Predicates and Liberation in Dutch and English.' To<br />

appear in Linguistics and Philosophy.


Keenan, E.L. (1989). 'Semantic Case Theory.' In: R. Bartsch, J. van Benthem, and P. van<br />

Emde Boas (eds.) Semantics and Contextual Expression. Dordrecht: Foris, 33-56.<br />

Keenan, E.L. and L.M. Faltz (1985). Boolean Semantics for Natural Language. Dordrecht:<br />

Reidel.<br />

Kraak, A. (1966). Negatiwe zinnen: een metlzodologirche en grammatkche anabse.<br />

Hilversum: W. de Haan.<br />

Partee, B. and M. Rooth (1983). 'Generalized Conjunction and Type Ambiguity.' In: R.<br />

Bauerle, C. Schwarze and A. von Stechow (eds.) Meaning, Use and Interpretation<br />

of Language. Berlin: de Gruyter, 361-383.<br />

Sikorski, R. (1969). Boolean Algebras. Third edition. Berlin: Springer.<br />

Sommers, F. (1982). The Logic of Natzual Language. Oxford: Clarendon Press.<br />

<strong>Zwarts</strong>, F. (1991). 'Reflexives and Other Matters.' In: M. Kas, E. Reuland, and C. Vet<br />

(eds.) Language and Cognition I. Groningen: Groningen University Press, 35 1-364.

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