====== Modus Camestros ======

Form of a [[glossary:syllogism|syllogism]] based on the [[logic:inferences:modus_celarent:index|Modus Celarent]], in which a negative [[glossary:universal_quantification|universal]] proposition is inferred from an affirmative and a negative [[glossary:existential_quantification|existential]] proposition.

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<h3>Modus Camestros</h3>{{modus_camestros.svg?nolink|Modus Camestros}}<figcaption>Type ''AEO'', Figure ''2''<span noprint> [[app>#AE2O|Modus Celaront]]</span> \\ Parent: [[logic:inferences:modus_celarent:index|Celarent]]</figcaption>
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> All <abbr "major term">P</abbr> are <abbr "middle term">M</abbr>.
> No <abbr "minor term">S</abbr> is <abbr "middle term">M</abbr>.
> [<i>and there exists at least one</i> <abbr "minor term">S</abbr>]*
> <span conclusio>Therefore, some <abbr "minor term">S</abbr> are not <abbr "major term">P</abbr>.</span>

For example:

> All <i>squares</i> are <i>rectangles</i>.
> No <i>circle</i> is a <i>rectangle</i>.
> [and there exists at least one <i>circle</i>]*
> <span conclusio>Therefore, some <em>circles</em> are not <em>squares</em>.</span>

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* **Note:** When an //existential// conclusion is inferred from //universal// premisses, this requires an (implicit or explicit) [[glossary:existential_import|existential import]], i.e. it must be proven that what the term refers to actually //exists//. In case of the //Modus Camestros// it is sufficient to prove existence for the //minor term// (<abbr "minor term">S</abbr>), as this also implies existence for <abbr "middle term">M</abbr>, while the conclusion does not actually require existence for <abbr "major term">P</abbr>.
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//Modus Camestros// is similar to [[logic:inferences:modus_celarent:modus_camestres|Modus Camestres]], but is the weaker of the two forms, as it infers a //existential// statement rather than an //universal// one.

===== Name =====

The name "Camestros" is a [[wp>Mnemonic|mnemonic]] term that helps to remember the most important characteristics of this mode: The "C" at the beginning indicates that it is related to the [[logic:inferences:modus_celarent:index|Modus Celarent]], the "a" and "e" mark the affirmative and negative [[glossary:universal_quantification|universal]] statements in the premisses, the "o" a negative [[glossary:existential_quantification|existential]] conclusion.

==== Alternative name ====

  * Modus Camestrop

===== See also =====

  * [[logic:formal_fallacies:existential|Existential fallacy]]
  * [[glossary:existential_import|Existential import]]
  * [[glossary:existential_quantification|Existential quantification]]
  * [[logic:inferences:modus_celarent:index|Modus Celarent]]
  * [[glossary:syllogism|Syllogism]]
  * [[glossary:universal_quantification|Universal Quantification]]

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