Modus Disamis
Form of a syllogism based on the Modus Darii, in which an affirmative existential proposition is inferred from affirmative universal and existential premisses.
Some M are P.
All M are S.
Therefore, Some S are P.
For example:
Some rectangles are squares.
All rectangles are polygons.
Therefore, Some polygons are squares.
Modus Disamis is very similar to Modus Darii, except that the term in the minor statement are reversed.
Name
The name “Disamis” is a 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 Modus Darii, the “a” and the two “i” indicate the affirmative universal and existential statements that make up this form.