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{{redirect|Universal quantifier|the symbol conventionally used for this quantifier|Turned A}}
 
In [[predicate logic]], a '''universal quantification''' is a type of [[quantification|quantifier]], a [[logical constant]] which is [[interpretation (logic)|interpreted]] as "given any" or "for all". It expresses that a [[propositional function]] can be [[satisfiability|satisfied]] by every [[element (mathematics)|member]] of a [[domain of discourse]]. In other terms, it is the [[Predicate (mathematical logic)|predication]] of a [[property (philosophy)|property]] or [[binary relation|relation]] to every member of the domain. It [[logical assertion|asserts]] that a predicate within the [[free variables and bound variables|scope]] of a universal quantifier is true of every [[Valuation (logic)|value]] of a [[predicate variable]].
 
It is usually denoted by the [[turned A]] (∀) [[logical connective|logical operator]] [[Symbol (formal)|symbol]], which, when used together with a predicate variable, is called a '''universal quantifier''' ("∀x", "∀(x)", or sometimes by  "(x)" alone). Universal quantification is distinct from [[existential quantification|''existential'' quantification]] ("there exists"), which asserts that the property or relation holds only for at least one member of the domain.
 
Quantification in general is covered in the article on [[quantification]]. Symbols are encoded {{unichar|2200|FOR ALL|note=as a mathematical symbol|html=|ulink=}}.
 
== Basics ==
Suppose it is given that
<blockquote>2·0 = 0 + 0, and 2·1 = 1 + 1, and 2·2 = 2 + 2, etc.</blockquote>
This would seem to be a [[logical conjunction]] because of the repeated use of "and." However, the "etc." cannot be interpreted as a conjunction in [[formal logic]]. Instead, the statement must be rephrased:
<blockquote>For all natural numbers ''n'', 2·''n'' = ''n'' + ''n''.</blockquote>
This is a single statement using universal quantification.
 
This statement can be said to be more precise than the original one. While the "etc." informally includes [[natural number]]s, and nothing more, this was not rigorously given. In the universal quantification, on the other hand, the natural numbers are mentioned explicitly.
 
This particular example is [[true (logic)|true]], because any natural number could be substituted for ''n'' and the statement "2·''n'' = ''n'' + ''n''" would be true. In contrast,
<blockquote>For all natural numbers ''n'', 2·''n'' > 2 + ''n''</blockquote>
is [[false (logic)|false]], because if ''n'' is substituted with, for instance, 1, the statement "2·1 > 2 + 1" is false. It is immaterial that "2·''n'' > 2 + ''n''" is true for ''most'' natural numbers ''n'': even the existence of a single [[counterexample]] is enough to prove the universal quantification false.
 
On the other hand,
for all [[composite number]]s ''n'', 2·''n'' > 2 + ''n''
is true, because none of the counterexamples are composite numbers. This indicates the importance of the ''[[domain of discourse]]'', which specifies which values ''n'' can take.<ref group="note">Further information on using domains of discourse with quantified statements can be found in the [[Quantification]] article.</ref> In particular, note that if the domain of discourse is restricted to consist only of those objects that satisfy a certain predicate, then for universal quantification this requires a [[logical conditional]]. For example,
<blockquote>For all composite numbers ''n'', 2·''n'' > 2 + ''n''</blockquote>
is [[logically equivalent]] to
<blockquote>For all natural numbers ''n'', if ''n'' is composite, then 2·''n'' > 2 + ''n''.</blockquote>  
Here the "if ... then" construction indicates the logical conditional.
 
=== Notation ===
In [[First-order logic|symbolic logic]], the universal quantifier symbol <math> \forall </math> (an [[turned A|inverted]]&nbsp;"[[A]]" in a [[sans-serif]] font, Unicode&nbsp;0x2200) is used to indicate universal quantification.<ref>The [[turned A|inverted&nbsp;"A"]] was used in the 19th century by [[Charles Sanders Peirce]] as a logical symbol for 'un-American' ("unamerican").
 
Page 320 in Randall Dipert, "[http://books.google.com/books?id=3suPBY5qh-cC&pg=PR7&dq=Cheryl+Misak,+unamerican&source=gbs_selected_pages&cad=3#v=onepage&q=unAmerican&f=false Peirce's deductive logic]". In Cheryl Misak, ed. ''The Cambridge Companion to Peirce''. 2004</ref>
 
For example, if ''P''(''n'') is the predicate "2·''n'' > 2 + ''n''" and '''N''' is the [[Set (mathematics)|set]] of natural numbers, then:
: <math> \forall n\!\in\!\mathbb{N}\; P(n) </math>
 
is the (false) statement:
<blockquote>For all natural numbers ''n'', 2·''n'' > 2 + ''n''.</blockquote>
 
Similarly, if ''Q''(''n'') is the predicate "''n'' is composite", then
: <math> \forall n\!\in\!\mathbb{N}\; \bigl( Q(n) \rightarrow  P(n) \bigr) </math>
 
is the (true) statement:
<blockquote>For all natural numbers ''n'', if ''n'' is composite, then 2·''n'' > 2 + n</blockquote>
 
and since "''n'' is composite" implies that ''n'' must already be a natural number, we can shorten this statement to the equivalent:
: <math> \forall n\; \bigl( Q(n) \rightarrow P(n) \bigr) </math>
 
<blockquote>For all composite numbers ''n'', 2·''n'' > 2 + ''n''.</blockquote>
 
Several variations in the notation for quantification (which apply to all forms) can be found in the [[quantification]] article. There is a special notation used only for universal quantification, which is given:
: <math> (n{\in}\mathbb{N})\, P(n) </math>
 
The parentheses indicate universal quantification by default.
 
== Properties ==
 
<!-- ''We need a list of algebraic properties of universal quantification, such as distributivity over conjunction, and so on. Also rules of inference.'' -->
 
===Negation===
Note that a quantified [[propositional function]] is a statement; thus, like statements, quantified functions can be negated. The notation most mathematicians and logicians utilize to denote negation is: <math>\lnot\ </math>. However, some (such as [[Douglas Hofstadter]]) use the [[tilde]] (~).
 
For example, if P(''x'') is the propositional function "x is married", then, for a [[Universe of discourse|Universe of Discourse]] X of all living human beings, the universal quantification
<blockquote>Given any living person ''x'', that person is married</blockquote>
is given:
:<math>\forall{x}{\in}\mathbf{X}\, P(x)</math>
 
It can be seen that this is irrevocably false. Truthfully, it is stated that
<blockquote>It is not the case that, given any living person ''x'', that person is married</blockquote>
or, symbolically:
:<math>\lnot\ \forall{x}{\in}\mathbf{X}\, P(x)</math>.
 
If the statement is not true for ''every'' element of the Universe of Discourse, then, presuming the universe of discourse is non-empty, there must be at least one element for which the statement is false. That is, the negation of <math>\forall{x}{\in}\mathbf{X}\, P(x)</math> is logically equivalent to "There exists a living person ''x'' such that he is not married", or:
:<math>\exists{x}{\in}\mathbf{X}\, \lnot P(x)</math>
 
Generally, then, the negation of a propositional function's universal quantification is an [[existential quantification]] of that propositional function's negation; symbolically,
:<math>\lnot\ \forall{x}{\in}\mathbf{X}\, P(x) \equiv\ \exists{x}{\in}\mathbf{X}\, \lnot P(x)</math>
 
It is erroneous to state "all persons are not married" (i.e. "there exists no person who is married") when it is meant that "not all persons are married" (i.e. "there exists a person who is not married"):
:<math>\lnot\ \exists{x}{\in}\mathbf{X}\, P(x) \equiv\ \forall{x}{\in}\mathbf{X}\, \lnot P(x) \not\equiv\ \lnot\ \forall{x}{\in}\mathbf{X}\, P(x) \equiv\ \exists{x}{\in}\mathbf{X}\, \lnot P(x)</math>
 
===Other connectives===
The universal (and existential) quantifier moves unchanged across the [[logical connective]]s [[logical conjunction|∧]], [[logical disjunction|∨]], [[material conditional|→]], and [[converse nonimplication|<math>\nleftarrow</math>]], as long as the other operand is not affected; that is:
:<math>P(x) \land (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \land Q(y))</math>
:<math>P(x) \lor  (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \lor Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \to  (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \to Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \nleftarrow (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \nleftarrow Q(y))</math>
:<math>P(x) \land (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \land Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \lor  (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \lor Q(y))</math>
:<math>P(x) \to  (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \to Q(y))</math>
:<math>P(x) \nleftarrow (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \nleftarrow Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
Conversely, for the logical connectives [[Sheffer stroke|↑]], [[Logical NOR|↓]], [[Material nonimplication|<math>\nrightarrow</math>]], and [[converse implication|←]], the quantifiers flip:
:<math>P(x) \uparrow (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \uparrow Q(y))</math>
:<math>P(x) \downarrow  (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \downarrow Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \nrightarrow (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \nrightarrow Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \gets (\exists{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \forall{y}{\in}\mathbf{Y}\, (P(x) \gets Q(y))</math>
:<math>P(x) \uparrow (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \uparrow Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
:<math>P(x) \downarrow  (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \downarrow Q(y))</math>
:<math>P(x) \nrightarrow (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \nrightarrow Q(y))</math>
:<math>P(x) \gets (\forall{y}{\in}\mathbf{Y}\, Q(y)) \equiv\ \exists{y}{\in}\mathbf{Y}\, (P(x) \gets Q(y)),~\mathrm{provided~that}~\mathbf{Y}\neq \emptyset</math>
 
<!-- What about:
*[[logical biconditional|Biconditional (if and only if) (xnor)]] (<math>\leftrightarrow</math>, <math>\equiv</math>, or <math>=</math>)
*[[Exclusive or|Exclusive disjunction (xor)]] (<math>\not\leftrightarrow</math>)
-->
 
=== Rules of inference ===
 
A [[rule of inference]] is a rule justifying a logical step from hypothesis to conclusion. There are several rules of inference which utilize the universal quantifier.
 
''[[Universal instantiation]]'' concludes that, if the propositional function is known to be universally true, then it must be true for any arbitrary element of the Universe of Discourse. Symbolically, this is represented as
 
:<math> \forall{x}{\in}\mathbf{X}\, P(x) \to\ P(c)</math>
 
where ''c'' is a completely arbitrary element of the Universe of Discourse.
 
''[[Generalization (logic)|Universal generalization]]'' concludes the propositional function must be universally true if it is true for any arbitrary element of the Universe of Discourse.  Symbolically, for an arbitrary ''c'',
 
:<math> P(c) \to\ \forall{x}{\in}\mathbf{X}\, P(x).</math>
 
The element&nbsp;''c'' must be completely arbitrary; else, the logic does not follow: if ''c'' is not arbitrary, and is instead a specific element of the Universe of Discourse, then P(''c'') only implies an existential quantification of the propositional function.
<!-- ''Discuss universally quantified types in [[type theory]].'' -->
 
=== The empty set ===
 
By convention, the formula <math>\forall{x}{\in}\emptyset \, P(x)</math> is always true, regardless of the formula ''P''(''x''); see [[vacuous truth]].
 
== Universal closure ==
 
The '''universal closure''' of a formula φ is the formula with no [[free variable]]s obtained by adding a universal quantifier for every free variable in φ. For example, the universal closure of
:<math>P(y) \land \exists x Q(x,z)</math>
is
:<math>\forall y \forall z ( P(y) \land \exists x Q(x,z))</math>.
 
== As adjoint ==
In [[category theory]] and the theory of [[elementary topos|elementary topoi]], the universal quantifier can be understood as the [[right adjoint]] of a [[functor]] between [[power set]]s, the [[inverse image]] functor of a function between sets; likewise, the [[existential quantifier]] is the [[left adjoint]].<ref>Saunders Mac Lane, Ieke Moerdijk, (1992) ''Sheaves in Geometry and Logic'' Springer-Verlag. ISBN 0-387-97710-4 ''See page 58''</ref>
 
For a set <math>X</math>, let <math>\mathcal{P}X</math> denote its [[powerset]]. For any function <math>f:X\to Y</math> between sets <math>X</math> and <math>Y</math>, there is an [[inverse image]] functor <math>f^*:\mathcal{P}Y\to \mathcal{P}X</math> between powersets, that takes subsets of the codomain of ''f'' back to subsets of its domain. The left adjoint of this functor is the existential quantifier <math>\exists_f</math> and the right adjoint is the universal quantifier <math>\forall_f</math>.
 
That is, <math>\exists_f\colon \mathcal{P}X\to \mathcal{P}Y</math> is a functor that, for each subset <math>S \subset X</math>, gives the subset <math>\exists_f S \subset Y</math> given by
:<math>\exists_f S =\{ y\in Y | \mbox{ there exists } x\in X \mbox{ s.t. } f(x)=y \}</math>.
Likewise, the universal quantifier <math>\forall_f\colon \mathcal{P}X\to \mathcal{P}Y</math> is given by
:<math>\forall_f S =\{ y\in Y | f(x)=y \mbox{ for all } x\in X \}</math>.
 
The more familiar form of the quantifiers as used in [[first-order logic]] is obtained by taking the function ''f'' to be the [[projection operator]] <math>\pi:X \times \{T,F\}\to \{T,F\}</math> where <math>\{T,F\}</math> is the two-element set holding the values true, false, and subsets ''S'' to be [[predicate (mathematical logic)|predicates]] <math>S\subset X\times \{T,F\}</math>, so that
:<math>\exists_\pi S = \{y\,|\,\exists x\, S(x,y)\}</math>
which is either a one-element set (false) or a two-element set (true).
 
The universal and existential quantifiers given above generalize to the [[presheaf category]].
 
== See also ==
{{Wiktionary|every}}
* [[Existential quantification]]
* [[Quantifier]]s
* [[First-order logic]]
* [[List of logic symbols]] - for the unicode symbol ∀
 
== Notes ==
<references group="note" />
 
==References==
{{Reflist}}
 
*{{cite book | author = Hinman, P. | title = Fundamentals of Mathematical Logic | publisher = [[A K Peters]] | year = 2005 | isbn = 1-56881-262-0}}
*{{cite book | author = [[James Franklin (philosopher)|Franklin, J.]] and Daoud, A. | title = Proof in Mathematics: An Introduction | url = http://www.maths.unsw.edu.au/~jim/proofs.html | publisher = Kew Books | year = 2011 | isbn = 978-0-646-54509-7}} (ch. 2)
 
[[Category:Quantification]]
[[Category:Logic symbols]]
[[Category:Logical expressions]]

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In predicate logic, a universal quantification is a type of quantifier, a logical constant which is interpreted as "given any" or "for all". It expresses that a propositional function can be satisfied by every member of a domain of discourse. In other terms, it is the predication of a property or relation to every member of the domain. It asserts that a predicate within the scope of a universal quantifier is true of every value of a predicate variable.

It is usually denoted by the turned A (∀) logical operator symbol, which, when used together with a predicate variable, is called a universal quantifier ("∀x", "∀(x)", or sometimes by "(x)" alone). Universal quantification is distinct from existential quantification ("there exists"), which asserts that the property or relation holds only for at least one member of the domain.

Quantification in general is covered in the article on quantification. Symbols are encoded Template:Unichar.

Basics

Suppose it is given that

2·0 = 0 + 0, and 2·1 = 1 + 1, and 2·2 = 2 + 2, etc.

This would seem to be a logical conjunction because of the repeated use of "and." However, the "etc." cannot be interpreted as a conjunction in formal logic. Instead, the statement must be rephrased:

For all natural numbers n, 2·n = n + n.

This is a single statement using universal quantification.

This statement can be said to be more precise than the original one. While the "etc." informally includes natural numbers, and nothing more, this was not rigorously given. In the universal quantification, on the other hand, the natural numbers are mentioned explicitly.

This particular example is true, because any natural number could be substituted for n and the statement "2·n = n + n" would be true. In contrast,

For all natural numbers n, 2·n > 2 + n

is false, because if n is substituted with, for instance, 1, the statement "2·1 > 2 + 1" is false. It is immaterial that "2·n > 2 + n" is true for most natural numbers n: even the existence of a single counterexample is enough to prove the universal quantification false.

On the other hand, for all composite numbers n, 2·n > 2 + n is true, because none of the counterexamples are composite numbers. This indicates the importance of the domain of discourse, which specifies which values n can take.[note 1] In particular, note that if the domain of discourse is restricted to consist only of those objects that satisfy a certain predicate, then for universal quantification this requires a logical conditional. For example,

For all composite numbers n, 2·n > 2 + n

is logically equivalent to

For all natural numbers n, if n is composite, then 2·n > 2 + n.

Here the "if ... then" construction indicates the logical conditional.

Notation

In symbolic logic, the universal quantifier symbol (an inverted "A" in a sans-serif font, Unicode 0x2200) is used to indicate universal quantification.[1]

For example, if P(n) is the predicate "2·n > 2 + n" and N is the set of natural numbers, then:

nP(n)

is the (false) statement:

For all natural numbers n, 2·n > 2 + n.

Similarly, if Q(n) is the predicate "n is composite", then

n(Q(n)P(n))

is the (true) statement:

For all natural numbers n, if n is composite, then 2·n > 2 + n

and since "n is composite" implies that n must already be a natural number, we can shorten this statement to the equivalent:

n(Q(n)P(n))

For all composite numbers n, 2·n > 2 + n.

Several variations in the notation for quantification (which apply to all forms) can be found in the quantification article. There is a special notation used only for universal quantification, which is given:

(n)P(n)

The parentheses indicate universal quantification by default.

Properties

Negation

Note that a quantified propositional function is a statement; thus, like statements, quantified functions can be negated. The notation most mathematicians and logicians utilize to denote negation is: ¬. However, some (such as Douglas Hofstadter) use the tilde (~).

For example, if P(x) is the propositional function "x is married", then, for a Universe of Discourse X of all living human beings, the universal quantification

Given any living person x, that person is married

is given:

xXP(x)

It can be seen that this is irrevocably false. Truthfully, it is stated that

It is not the case that, given any living person x, that person is married

or, symbolically:

¬xXP(x).

If the statement is not true for every element of the Universe of Discourse, then, presuming the universe of discourse is non-empty, there must be at least one element for which the statement is false. That is, the negation of xXP(x) is logically equivalent to "There exists a living person x such that he is not married", or:

xX¬P(x)

Generally, then, the negation of a propositional function's universal quantification is an existential quantification of that propositional function's negation; symbolically,

¬xXP(x)xX¬P(x)

It is erroneous to state "all persons are not married" (i.e. "there exists no person who is married") when it is meant that "not all persons are married" (i.e. "there exists a person who is not married"):

¬xXP(x)xX¬P(x)≢¬xXP(x)xX¬P(x)

Other connectives

The universal (and existential) quantifier moves unchanged across the logical connectives , , , and , as long as the other operand is not affected; that is:

P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY

Conversely, for the logical connectives , , , and , the quantifiers flip:

P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y))
P(x)(yYQ(y))yY(P(x)Q(y)),providedthatY


Rules of inference

A rule of inference is a rule justifying a logical step from hypothesis to conclusion. There are several rules of inference which utilize the universal quantifier.

Universal instantiation concludes that, if the propositional function is known to be universally true, then it must be true for any arbitrary element of the Universe of Discourse. Symbolically, this is represented as

xXP(x)P(c)

where c is a completely arbitrary element of the Universe of Discourse.

Universal generalization concludes the propositional function must be universally true if it is true for any arbitrary element of the Universe of Discourse. Symbolically, for an arbitrary c,

P(c)xXP(x).

The element c must be completely arbitrary; else, the logic does not follow: if c is not arbitrary, and is instead a specific element of the Universe of Discourse, then P(c) only implies an existential quantification of the propositional function.

The empty set

By convention, the formula xP(x) is always true, regardless of the formula P(x); see vacuous truth.

Universal closure

The universal closure of a formula φ is the formula with no free variables obtained by adding a universal quantifier for every free variable in φ. For example, the universal closure of

P(y)xQ(x,z)

is

yz(P(y)xQ(x,z)).

As adjoint

In category theory and the theory of elementary topoi, the universal quantifier can be understood as the right adjoint of a functor between power sets, the inverse image functor of a function between sets; likewise, the existential quantifier is the left adjoint.[2]

For a set X, let 𝒫X denote its powerset. For any function f:XY between sets X and Y, there is an inverse image functor f*:𝒫Y𝒫X between powersets, that takes subsets of the codomain of f back to subsets of its domain. The left adjoint of this functor is the existential quantifier f and the right adjoint is the universal quantifier f.

That is, f:𝒫X𝒫Y is a functor that, for each subset SX, gives the subset fSY given by

fS={yY| there exists xX s.t. f(x)=y}.

Likewise, the universal quantifier f:𝒫X𝒫Y is given by

fS={yY|f(x)=y for all xX}.

The more familiar form of the quantifiers as used in first-order logic is obtained by taking the function f to be the projection operator π:X×{T,F}{T,F} where {T,F} is the two-element set holding the values true, false, and subsets S to be predicates SX×{T,F}, so that

πS={y|xS(x,y)}

which is either a one-element set (false) or a two-element set (true).

The universal and existential quantifiers given above generalize to the presheaf category.

See also

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Firstly, a Fraudulent Misrepresentation is one that is made knowingly by the Representor that it was false or if it was made without belief in its fact or made recklessly without concerning whether or not it is true or false. For instance estate agent A told the potential consumers that the tenure of a landed property they are considering is freehold when it is really one with a ninety nine-yr leasehold! A is responsible of constructing a fraudulent misrepresentation if he is aware of that the tenure is the truth is a ninety nine-yr leasehold instead of it being freehold or he didn't consider that the tenure of the house was freehold or he had made the assertion with out caring whether or not the tenure of the topic property is in fact freehold.

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Notice that the application must be submitted by the appointed Key Government Officer (KEO) such as the CEO, COO, or MD. Once the KEO has submitted the mandatory paperwork and assuming all documents are in order, an email notification shall be sent stating that the applying is permitted. No hardcopy of the license might be issued. A delicate-copy could be downloaded and printed by logging into the CEA website. It takes roughly four-6 weeks to course of an utility.

Notes

  1. Further information on using domains of discourse with quantified statements can be found in the Quantification article.

References

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  • 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.

    My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 (ch. 2)
  1. The inverted "A" was used in the 19th century by Charles Sanders Peirce as a logical symbol for 'un-American' ("unamerican"). Page 320 in Randall Dipert, "Peirce's deductive logic". In Cheryl Misak, ed. The Cambridge Companion to Peirce. 2004
  2. Saunders Mac Lane, Ieke Moerdijk, (1992) Sheaves in Geometry and Logic Springer-Verlag. ISBN 0-387-97710-4 See page 58