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Quantifier shift

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A logical fallacy in which the quantifiers of a statement are erroneously transposed.

Definition

For every A, there is a B, such that C. Therefore, there is a B, such that for every A, C.

x y(Rxy) therefore yx(Rxy)
OR

There is an A, such that for every B, C. Therefore, for every B, there is an A, such that C.

yx(Rxy) therefore x y(Rxy)

Examples

Every person has a woman that is their mother. Therefore, there is a woman that is the mother of every person.

xy((Px Wy & M(yx)

Everybody has something to believe in. Therefore, there is something that everybody believes in.