====== Modus Datisi ======

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

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<h3>Modus Datisi</h3>
{{modus_datisi.svg?nolink|Modus Datisi}}
<figcaption>Type ''AII'', Figure ''3''<span noprint> [[app>#AI3I|Modus Datisi]]</span> \\ Parent: [[logic:inferences:modus_darii:index|Darii]]</figcaption>
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> All <abbr title="middle term">M</abbr> are <abbr title="major term">P</abbr>.
> Some <abbr title="middle term">M</abbr> are <abbr title="minor term">S</abbr>.
> <span conclusio>Therefore, Some <abbr title="minor term">S</abbr> are <abbr title="major term">P</abbr>.</span>

For example:

> All <var>rectangles</var> are <var>polygons</var>.
> Some <var>rectangles</var> are <var>squares</var>.
> <span conclusio>Therefore, Some <var>squares</var> are <var>polygons</var>.</span>

//Modus Datisi// is very similar to [[logic:inferences:modus_darii:index|Modus Darii]], the only difference being that the terms in the //minor// statement are reversed.

===== Name =====

The name "Datisi" is a [[wp>Mnemonic|mnemonic]] term that helps to remember the most important characteristics of this mode: The "D" at the beginning indicates that it is related to the [[logic:inferences:modus_darii:index|Modus Darii]], the "a" and the two "i" indicate the affirmative [[glossary:universal_quantification|universal]] and [[glossary:existential_quantification|existential]]  statements that make up this form.

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

  * [[glossary:existential_quantification|Existential Quantification]]
  * [[logic:inferences:modus_darii:index|Modus Darii]]
  * [[glossary:syllogism|Syllogism]]
  * [[glossary:universal_quantification|Universal Quantification]]

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