Modus Fresison

Form of a syllogism based on the Modus Ferio, in which a negative existential proposition is inferred from negative universal and affirmative existential premisses.

No P is M.

Some M are S.

∴ Some S are not P.

For example:

No circle is a rectangle.

Some rectangles are squares.

∴ Some squares are not circles.

Modus Fresison is very similar to Modus Ferio, the only difference is that in both premisses the terms are swapped.

The name “Fresison” is a mnemonic term that helps to remember the most important characteristics of this mode: The “F” at the beginning indicates that it is related to the Modus Ferio, while the vowels indicate the types of statements used in the form: “e” stands for a negative universal, the “i” for an affirmative existential premise, while the “o” indicates an affirmative existential conclusion.

• Existential Quantification
• Modus Ferio
• Syllogism
• Universal Quantification