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| In [[logic]], the '''converse''' of a categorical or implicational statement is the result of reversing its two parts. For the [[Material conditional|implication]] ''P'' → ''Q'', the converse is ''Q'' → ''P''. For the [[categorical proposition]] ''All S is P'', the converse is ''All P is S''. In neither case does the converse [[logical consequence|necessarily follow]] from the original statement.<ref name="Audi">Robert Audi, ed. (1999), ''The Cambridge Dictionary of Philosophy'', 2nd ed., Cambridge University Press: "converse".</ref> The categorical converse of a statement is contrasted with the [[contraposition|contrapositive]] and the [[obversion|obverse]].
| | If you want to accelerate a PC then we have come to the right destination. I will show we, today, five quick methods which you can drastically boost your computer's performance.<br><br>Before really ordering the software it is best to check found on the businesses that make the software. If you will find details on the form of standing each firm has, possibly the risk of malicious programs is reduced. Software from reputed companies have aided me, plus various other consumers, to make my PC run quicker.. If the product description refuses to look good to you, refuses to include details about the software, refuses to include the scan functions, you should go for another 1 which ensures you're paying for what we wish.<br><br>So what should you look for whenever we compare registry products. Many of the registry products available now, have very similar features. The primary ones which you need to be lookin for are these.<br><br>If that does not work you should try and repair the issue with a 'registry cleaner'. What happens on various computers is that their registry database becomes damaged plus unable to show the computer where the DLL files that it requirements are. Every Windows PC has a central 'registry' database that stores information about all the DLL files on the computer.<br><br>One other way when arresting the 1328 error is to clean out the PC's registry. The registry is important as it is actually where settings and files chosen by Windows for operating are stored. As it's frequently employed, breakdowns plus instances of files getting corrupted are not uncommon. Additionally due to the method it is very configured, the "registry" gets saved in the incorrect fashion frequently, that makes your program run slow, eventually causing a PC to suffer from a series of errors. The most effective method 1 may use inside cleaning out registries is to use a reliable [http://bestregistrycleanerfix.com/tune-up-utilities tuneup utilities] system. A registry cleaner can find out and repair corrupted registry files and settings allowing one's computer to run normally again.<br><br>The most probable cause of the trouble is the program issue - Registry Errors! That is the reason why folks that absolutely have over 2 G RAM on their computers are nonetheless constantly bothered by the problem.<br><br>Another problem with all the damaged variation is the fact that it takes too much time to scan the program plus whilst it's scanning, we cannot use the computer otherwise. Moreover, there is not any technical help to these damaged versions which means should you receive stuck someplace, you can't ask for help. They even do not have any customer service help lines wherein we could call or send to resolve the issues.<br><br>You are able to click here to locate out how to accelerate Windows and heighten PC perfomance. And you can click here to download a registry cleaner to aid you clean up registry. |
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| ==Implicational converse==
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| ''S'' is a statement of the form ''P implies Q'' (''P'' → ''Q''), then the '''converse''' of ''S'' is the statement ''Q implies P'' (''Q'' → ''P''). In general, the verity of ''S'' says nothing about the verity of its converse, unless the [[Antecedent (logic)|antecedent]] ''P'' and the [[consequent]] ''Q'' are logically equivalent.
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| For example, consider the true statement "If I am a human, then I am mortal." The converse of that statement is "If I am mortal, then I am a human," which is not [[logical truth|necessarily true]].
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| On the other hand, the converse of a statement with mutually inclusive terms remains true, given the truth of the original proposition. Thus, the statement "If I am a bachelor, then I am an unmarried man" is logically equivalent to "If I am an unmarried man, then I am a bachelor."
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| A truth table makes it clear that ''S'' and the converse of ''S'' are not logically equivalent unless both terms imply each other:
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| {| class="wikitable"
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| ! ''P'' || ''Q'' || ''P'' → ''Q'' || ''Q'' → ''P'' (converse)
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| |-
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| | T || T || T || T
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| |-
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| | T || F || F || T
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| |-
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| | F || T || T || F
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| |-
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| | F || F || T || T
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| |}
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| Going from a statement to its converse is the fallacy of [[affirming the consequent]]''''' ''S'' and its converse are equivalent (i.e. if ''P'' is true [[iff|if and only if]] ''Q'' is also true), then affirming the consequent will be valid.
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| ===Converse of a theorem===
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| In mathematics, the converse of a theorem of the form ''P'' → ''Q'' will be ''Q'' → ''P''. The converse may or may not be true. If true, the proof may be difficult. For example, the [[Four-vertex theorem]] was proved in 1912, but its converse only in 1998.
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| In practice, when determining the converse of a mathematical theorem, aspects of the antecedent may be taken as establishing context. That is, the converse of ''Given P, if Q then R'' will be ''Given P, if R then Q''. For example, the [[Pythagorean theorem]] can be stated as:
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| <blockquote> | |
| '''Given''' a triangle with sides of length ''a'', ''b'', and ''c'', '''if''' the angle opposite the side of length ''c'' is a right angle, '''then''' '''''a''<sup>2</sup> + ''b''<sup>2</sup> = ''c''<sup>2</sup>.
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| </blockquote>
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| The converse, which also appears in [[Euclid's Elements|Euclid's ''Elements'']] (Book I, Proposition 48), can be stated as: | |
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| <blockquote> | |
| '''Given''' a triangle with sides of length ''a'', ''b'', and ''c'', '''if''' ''a''<sup>2</sup> + ''b''<sup>2</sup> = ''c''<sup>2</sup>, '''then''' the angle opposite the side of length ''c'' is a right angle.
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| </blockquote>
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| ==Categorical converse==
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| In traditional logic, the process of going from ''All S are P'' to its converse ''All P are S'' is called '''conversion'''. In the words of [[Asa Mahan]], "The original proposition is called the exposita; when converted, it is denominated the converse. Conversion is valid when, and only when, nothing is asserted in the converse which is not affirmed or implied in the exposita."<ref>Asa Mahan (1857), The Science of Logic: or, An Analysis of the Laws of Thought, [http://books.google.com/books?id=J_wtAAAAMAAJ&pg=PA82 p. 82].</ref> The "exposita" is more usually called the "convertend." In its simple form, conversion is valid only for '''E''' and '''I''' propositions:<ref>William Thomas Parry and Edward A. Hacker (1991), ''Aristotelian Logic'', SUNY Press, [http://books.google.com/books?id=3Sg84H6B-m4C&pg=PA207 p. 207].</ref>
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| {| class="wikitable"
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| ! Type || Convertend || Simple converse || Converse ''per accidens''
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| | '''A''' || All S are P || ''not valid'' || Some P is S
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| | '''E''' || No S is P || No P is S || Some P is not S
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| |-
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| | '''I''' || Some S is P || Some P is S || –
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| |-
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| | '''O''' || Some S is not P || ''not valid'' || –
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| |}
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| The validity of simple conversion only for '''E''' and '''I''' propositions can be expressed by the restriction that "No term must be distributed in the converse which is not distributed in the convertend."<ref>[[James H. Hyslop]] (1892), ''The Elements of Logic'', C. Scribner's sons, p. 156.</ref> For '''E''' propositions, both subject and predicate are [[Distribution of terms|distributed]], while for '''I''' propositions, neither is.
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| For '''A''' propositions, the subject is distributed while the predicate is not, and so the inference from an '''A''' statement to its converse is not valid. As an example, for the '''A''' proposition "All cats are mammals," the converse "All mammals are cats" is obviously false. However, the weaker statement "Some mammals are cats" is true. Logicians define conversion ''per accidens'' to be the process of producing this weaker statement. Inference from a statement to its converse ''per accidens'' is generally valid. However, as with [[syllogism]]s, this switch from the universal to the particular causes problems with empty categories: "All unicorns are mammals" is often taken as true, while the converse ''per accidens'' "Some mammals are unicorns" is clearly false.
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| In [[First-order logic|first-order predicate calculus]], ''All S are P'' can be represented as <math>\forall x. S(x) \to P(x)</math>.<ref>Gordon Hunnings (1988), ''The World and Language in Wittgenstein's Philosophy'', SUNY Press, [http://books.google.com/books?id=5XXz7B2PLRsC&pg=PA42 p. 42].</ref> It is therefore clear that the categorical converse is closely related to the implicational converse, and that ''S'' and ''P'' cannot be swapped in ''All S are P''.
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| ==See also==
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| {{Portal|Logic}}
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| {{col-begin}}
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| {{col-break}}
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| * [[Aristotle]]
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| * [[Contraposition]]
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| * [[Inference]]
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| * [[Obversion]]
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| * [[Syllogism]]
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| {{col-break}}
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| * [[Converse (semantics)]]
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| * [[Term logic]]
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| * [[Transposition (logic)]]
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| * [[Inverse (logic)]]
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| {{col-end}}
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| ==References==
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| {{reflist}}
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| ==Further reading==
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| *[[Aristotle]]. ''Organon''.
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| *[[Irving Copi|Copi, Irving]]. ''Introduction to Logic''. MacMillan, 1953.
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| *Copi, Irving. ''Symbolic Logic''. MacMillan, 1979, fifth edition.
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| *[[Susan Stebbing|Stebbing, Susan]]. ''A Modern Introduction to Logic''. Cromwell Company, 1931.
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| [[Category:Immediate inference]]
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If you want to accelerate a PC then we have come to the right destination. I will show we, today, five quick methods which you can drastically boost your computer's performance.
Before really ordering the software it is best to check found on the businesses that make the software. If you will find details on the form of standing each firm has, possibly the risk of malicious programs is reduced. Software from reputed companies have aided me, plus various other consumers, to make my PC run quicker.. If the product description refuses to look good to you, refuses to include details about the software, refuses to include the scan functions, you should go for another 1 which ensures you're paying for what we wish.
So what should you look for whenever we compare registry products. Many of the registry products available now, have very similar features. The primary ones which you need to be lookin for are these.
If that does not work you should try and repair the issue with a 'registry cleaner'. What happens on various computers is that their registry database becomes damaged plus unable to show the computer where the DLL files that it requirements are. Every Windows PC has a central 'registry' database that stores information about all the DLL files on the computer.
One other way when arresting the 1328 error is to clean out the PC's registry. The registry is important as it is actually where settings and files chosen by Windows for operating are stored. As it's frequently employed, breakdowns plus instances of files getting corrupted are not uncommon. Additionally due to the method it is very configured, the "registry" gets saved in the incorrect fashion frequently, that makes your program run slow, eventually causing a PC to suffer from a series of errors. The most effective method 1 may use inside cleaning out registries is to use a reliable tuneup utilities system. A registry cleaner can find out and repair corrupted registry files and settings allowing one's computer to run normally again.
The most probable cause of the trouble is the program issue - Registry Errors! That is the reason why folks that absolutely have over 2 G RAM on their computers are nonetheless constantly bothered by the problem.
Another problem with all the damaged variation is the fact that it takes too much time to scan the program plus whilst it's scanning, we cannot use the computer otherwise. Moreover, there is not any technical help to these damaged versions which means should you receive stuck someplace, you can't ask for help. They even do not have any customer service help lines wherein we could call or send to resolve the issues.
You are able to click here to locate out how to accelerate Windows and heighten PC perfomance. And you can click here to download a registry cleaner to aid you clean up registry.