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| [[File:Formal languages.svg|thumb|300px|right|This diagram shows the syntactic entities which may be constructed from [[formal language]]s.<ref>[http://dictionary.reference.com/browse/syntax Dictionary Definition]</ref> The [[symbol (formal)|symbols]] and [[string (computer science)|strings of symbols]] may be broadly divided into [[nonsense]] and [[well-formed formula]]s. A formal language is identical to the set of its well-formed formulas. The set of well-formed formulas may be broadly divided into [[theorem]]s and non-theorems.]]
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| In [[logic]], '''syntax''' is anything having to do with [[formal language]]s or [[formal system]]s without regard to any [[interpretation (logic)|interpretation]] or [[meaning (linguistics)|meaning]] given to them. Syntax is concerned with the rules used for constructing, or transforming the symbols and words of a language, as contrasted with the [[Formal semantics (logic)|semantics]] of a language which is concerned with its meaning.
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| The [[symbol (formal)|symbols]], [[well-formed formula|formulas]], [[formal system|system]]s, [[theorem]]s, [[formal proof|proofs]], and [[interpretation (logic)|interpretations]] expressed in formal languages are syntactic entities whose properties may be studied without regard to any meaning they may be given, and, in fact, need not be given any. | | The trouble when anything at all will become well-known is that is will be faked. This is especially the situation with womens footwear and boots as they are likely to be high priced and people today are always on the look out for a more cost-effective alternative to the real matter. This especially accurate when it comes to purchasing UGG boots. Even so, if you are searching for the genuine thing then it can be incredibly disheartening if you portion with your dollars only to obtain a fake duplicate of the product or service. <br><br>The issue is that the world-wide-web has produced it all much too easy for fraudsters to promote inexpensive imitations as the actual point and as you cant completely inspect them before obtaining a whole lot of people conclude up being really disappointed, not to point out ripped off! On the other hand, it is up to the buyer to have their wits about then when creating buys if a offer appears also excellent to be accurate it commonly is! When the serious UGG boots can get such higher price ranges why would there ever be a need to have for the genuine item to be offered at a steep discount? <br><br>That remaining said, a lot of consumers do tumble for the entice of a cut price and only conclude up remaining upset. Some others nonetheless, dont treatment if they do not get the actual deal and as prolonged as it appears shut sufficient then they are pleased! However, counterfeits do not previous for the very same length of time that the actual factor does, as a result you are very likely to hold on to these for a lot a lot less time. <br><br>The UGG boot has quick develop into a person of the most copied goods close to the globe. The actual issues are from Australia and are very heat with a furry lining made out of sheeps wool. You can recognise faux UGGs from genuine kinds as fakes use low cost synthetic fur that doesnt have the same really feel or color. The bogus items are likely to use a whole lot of man-built elements and therefore have a slight chemical smell that you dont get with true boots. <br><br>If you location a Produced In China label then this doesnt necessarily indicate that your boot are faux. Equally Typical and Shorter UGGs must have these labels. Having said that, if they do have a Produced in New Zealand label then they will be fakes, only the Ultra Sundances Dusk boots are produced right here. <br><br>A superior indication of whether the boots are authentic or phony is to seem at the soles. Real UGGs will have an R in a circle (this is the registered mark) subsequent to the UGG but this will be lacking on a fake. If you have reliable boots then the join amongst the sole and heel will be flush, and the UGG label will be embossed and not just printed. <br><br>There are cases wherever you may well obtain boots that show up real in all other areas but are remaining offered at a much decrease selling price that normal. These are seconds, basically. Check the label if they have 1, this really should be torn as a way of indicating that they are not great. They should also have the beige treatment card and insert. <br><br>Make absolutely sure you appear out for these critical signals and you really should protect by yourself from obtaining fakes. Actual UGG boots glimpse fantastic, are comfortable and will final for many years but fakes will speedily slide aside so make the expenditure and usually get the serious matter! <br><br>For more posts like this stop by Post Alley.<br><br>If you loved this post and you want to receive more details with regards to [http://tinyurl.com/m2okfad ugg sale] please visit our internet site. |
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| Syntax is usually associated with the rules (or grammar) governing the composition of texts in a formal language that constitute the [[well-formed formula]]s of a formal system.
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| In [[computer science]], the term [[Syntax of programming languages|syntax]] refers to the rules governing the composition of meaningful texts in a formal language, such as a [[programming language]], that is, those texts for which it makes sense to define the [[semantics]] or meaning, or otherwise provide an interpretation.<ref>[http://www.springerlink.com/content/7v73224742613266/ Abstract Syntax and Logic Programming]</ref>
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| == Syntactic entities ==
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| === Symbols ===
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| {{Main|Symbol (formal)}}
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| A symbol is an [[idea]], [[abstraction]] or [[concept]], [[Type-token distinction|tokens]] of which may be marks or a configuration of marks which form a particular pattern. Symbols of a formal language need not be symbols of anything. For instance there are [[logical constant]]s which do not refer to any idea, but rather serve as a form of punctuation in the language (e.g. parentheses). A symbol or string of symbols may comprise a well-formed formula if the formulation is consistent with the formation rules of the language. Symbols of a formal language must be capable of being specified without any reference to any interpretation of them.
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| === Formal language ===
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| {{Main|Formal language}}
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| A ''formal language'' is a syntactic entity which consists of a [[Set (mathematics)|set]] of finite [[string (computer science)|strings]] of [[symbol (formal)|symbol]]s which are its words (usually called its [[well-formed formula]]s). Which strings of symbols are words is determined by fiat by the creator of the language, usually by specifying a set of [[formation rule]]s. Such a language can be defined without [[reference]] to any [[meaning (linguistics)|meaning]]s of any of its expressions; it can exist before any [[Interpretation (logic)|interpretation]] is assigned to it – that is, before it has any meaning.
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| === Formation rules ===
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| {{main|Formation rule}}
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| ''Formation rules'' are a precise description of which [[string (computer science)|strings]] of [[symbol (formal)|symbol]]s are the [[well-formed formula]]s of a formal language. It is synonymous with the set of [[String (computer science)|strings]] over the [[alphabet]] of the formal language which constitute well formed formulas. However, it does not describe their [[semantics]] (i.e. what they mean).
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| === Propositions ===
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| {{main|Proposition}}
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| A '''proposition''' is a [[Sentence (linguistics)|sentence]] expressing something [[truth|true]] or [[falsity|false]]. A proposition is identified [[ontology|ontologically]] as an [[idea]], [[concept]] or [[abstraction]] whose [[type-token distinction|token instances]] are patterns of [[symbol (formal)|symbols]], marks, sounds, or [[string (computer science)|strings]] of [[words]].<ref>Metalogic, [[Geoffrey Hunter (logician)|Geoffrey Hunter]]</ref> Propositions are considered to be syntactic entities and also [[truthbearer]]s.
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| === Formal theories ===
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| {{main|Theory (mathematical logic)}}
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| A '''formal theory''' is a [[set (mathematics)|set]] of [[sentence (mathematical logic)|sentence]]s in a [[formal language]].
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| === Formal systems ===
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| {{main|Formal system}}
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| A ''formal system'' (also called a ''logical calculus'', or a ''logical system'') consists of a formal language together with a [[deductive apparatus]] (also called a ''deductive system''). The deductive apparatus may consist of a set of [[transformation rule]]s (also called ''inference rules'') or a set of [[axiom]]s, or have both. A formal system is used to derive one expression from one or more other expressions. Formal systems, like other syntactic entities may be defined without any [[Interpretation (logic)|interpretation]] given to it (as being, for instance, a system of arithmetic).
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| ==== Syntactic consequence within a formal system ====
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| A formula A is a '''syntactic consequence'''<ref>http://books.google.com/books?id=EYP7uCZIRQYC&pg=PA82&lpg=PA82&dq=syntactic+consequence&source=bl&ots=Ms58438B6w&sig=FE38FCaZpRpAr18gtG7INX4wieM&hl=en&ei=qOy7SoLlEI7KsQPgnYG7BA&sa=X&oi=book_result&ct=result&resnum=6#v=onepage&q=syntactic%20consequence&f=false</ref><ref>http://books.google.com/books?id=lXI7AAAAIAAJ&pg=PA1&lpg=PA1&dq=syntactic+consequence&source=bl&ots=8IYWyFYTN-&sig=wrOg75cFxQwn1Uq-8LShBNXf9w0&hl=en&ei=I-y7SpHtLZLotgOsnLHcBQ&sa=X&oi=book_result&ct=result&resnum=10#v=onepage&q=syntactic%20consequence&f=false</ref><ref>http://books.google.com/books?id=87BcFLgJmxMC&pg=PA189&lpg=PA189&dq=syntactic+consequence&source=bl&ots=Fn2zomcMZP&sig=8hnJWsJFysNhmWLskICo4IQDYAc&hl=en&ei=I-y7SpHtLZLotgOsnLHcBQ&sa=X&oi=book_result&ct=result&resnum=6#v=onepage&q=syntactic%20consequence&f=false</ref><ref>http://www.swif.uniba.it/lei/foldop/foldoc.cgi?syntactic+consequence</ref> within some formal system <math> \mathcal{FS}</math> of a set Г of formulas if there is a [[Formal proof|derivation]] in [[formal system]] <math> \mathcal{FS}</math> of A from the set Г.
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| :<math>\Gamma \vdash_{\mathrm FS} A</math>
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| Syntactic consequence does not depend on any [[interpretation (logic)|interpretation]] of the formal system.<ref>Hunter, Geoffrey, Metalogic: An Introduction to the Metatheory of Standard First-Order Logic, University of California Pres, 1971, p. 75.</ref>
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| ==== Syntactic completeness of a formal system ====
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| {{Main|Completeness}}
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| A formal system <math> \mathcal{S}</math> is ''syntactically complete''<ref>http://jigpal.oxfordjournals.org/cgi/reprint/11/5/513.pdf</ref><ref>http://portal.acm.org/citation.cfm?id=504575</ref><ref>http://books.google.com/books?id=CHfgmt4w5QEC&pg=PA236&lpg=PA236&dq=syntactic+completeness&source=bl&ots=WmLkbHF-uj&sig=reo9rQk1NWySJEmRY5JTBbIgkXY&hl=en&ei=TPG7SrjFFJLUsQOJ-encBQ&sa=X&oi=book_result&ct=result&resnum=4#v=onepage&q=syntactic%20completeness&f=false</ref><ref>http://www.swif.uniba.it/lei/foldop/foldoc.cgi?syntactic+completeness</ref> (also ''deductively complete'', ''maximally complete'', ''negation complete'' or simply ''complete'') iff for each formula A of the language of the system either A or ¬A is a theorem of <math> \mathcal{S}</math>. In another sense, a formal system is syntactically complete iff no unprovable axiom can be added to it as an axiom without introducing an [[consistency|inconsistency]]. Truth-functional [[propositional logic]] and first-order [[predicate logic]] are semantically complete, but not syntactically complete (for example the propositional logic statement consisting of a single variable "a" is not a theorem, and neither is its negation, but these are not [[tautology (logic)|tautologies]]). [[Gödel's incompleteness theorem]] shows that no [[recursive system]] that is sufficiently powerful, such as the [[Peano axioms]], can be both consistent and complete.
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| === Interpretations ===
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| {{main|Formal semantics (logic)|Interpretation (logic)}}
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| An ''interpretation'' of a formal system is the assignment of meanings to the symbols, and [[truth value]]s to the sentences of a formal system. The study of interpretations is called [[Formal semantics (logic)|formal semantics]]. ''Giving an interpretation'' is synonymous with ''constructing a [[Structure (mathematical logic)|model]]''. An interpretation is expressed in a [[metalanguage]], which may itself be a formal language, and as such itself is a syntactic entity.
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| ==References==
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| {{reflist}}
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| ==See also==
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| * [[Symbol (formal)]]
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| * [[Formation rule]]
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| * [[Formal grammar]]
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| * [[Syntax|Syntax (linguistics)]]
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| * [[Syntax (programming languages)]]
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| * [[Mathematical logic]]
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| * [[Well-formed formula]]
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| {{Logic}}
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| {{DEFAULTSORT:Syntax (Logic)}}
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| [[Category:Formal languages]]
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| [[Category:Metalogic]]
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| [[Category:Concepts in logic]]
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| [[Category:Syntax (logic)| ]]
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| [[Category:Philosophy of logic]]
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The trouble when anything at all will become well-known is that is will be faked. This is especially the situation with womens footwear and boots as they are likely to be high priced and people today are always on the look out for a more cost-effective alternative to the real matter. This especially accurate when it comes to purchasing UGG boots. Even so, if you are searching for the genuine thing then it can be incredibly disheartening if you portion with your dollars only to obtain a fake duplicate of the product or service.
The issue is that the world-wide-web has produced it all much too easy for fraudsters to promote inexpensive imitations as the actual point and as you cant completely inspect them before obtaining a whole lot of people conclude up being really disappointed, not to point out ripped off! On the other hand, it is up to the buyer to have their wits about then when creating buys if a offer appears also excellent to be accurate it commonly is! When the serious UGG boots can get such higher price ranges why would there ever be a need to have for the genuine item to be offered at a steep discount?
That remaining said, a lot of consumers do tumble for the entice of a cut price and only conclude up remaining upset. Some others nonetheless, dont treatment if they do not get the actual deal and as prolonged as it appears shut sufficient then they are pleased! However, counterfeits do not previous for the very same length of time that the actual factor does, as a result you are very likely to hold on to these for a lot a lot less time.
The UGG boot has quick develop into a person of the most copied goods close to the globe. The actual issues are from Australia and are very heat with a furry lining made out of sheeps wool. You can recognise faux UGGs from genuine kinds as fakes use low cost synthetic fur that doesnt have the same really feel or color. The bogus items are likely to use a whole lot of man-built elements and therefore have a slight chemical smell that you dont get with true boots.
If you location a Produced In China label then this doesnt necessarily indicate that your boot are faux. Equally Typical and Shorter UGGs must have these labels. Having said that, if they do have a Produced in New Zealand label then they will be fakes, only the Ultra Sundances Dusk boots are produced right here.
A superior indication of whether the boots are authentic or phony is to seem at the soles. Real UGGs will have an R in a circle (this is the registered mark) subsequent to the UGG but this will be lacking on a fake. If you have reliable boots then the join amongst the sole and heel will be flush, and the UGG label will be embossed and not just printed.
There are cases wherever you may well obtain boots that show up real in all other areas but are remaining offered at a much decrease selling price that normal. These are seconds, basically. Check the label if they have 1, this really should be torn as a way of indicating that they are not great. They should also have the beige treatment card and insert.
Make absolutely sure you appear out for these critical signals and you really should protect by yourself from obtaining fakes. Actual UGG boots glimpse fantastic, are comfortable and will final for many years but fakes will speedily slide aside so make the expenditure and usually get the serious matter!
For more posts like this stop by Post Alley.
If you loved this post and you want to receive more details with regards to ugg sale please visit our internet site.