存在量词 ``∃`` （ ``\ex`` ）用于表示短语“存在” 。Lean 中的形式表达式 ``∃ x : ℝ, 2 < x ∧ x < 3`` 是说存在一个介于2到3 ...

Wh-words have been analysed as existential quantifiers (Chierchia in Logic in grammar: polarity, free choice, and intervention. Oxford University Press, Oxford, 2013; Fox, in Sauerland U, Stateva P ...

Abstract: We consider the problem of existential quantifier elimination for Boolean CNF formulas. We present a new method for solving this problem called Derivation of Dependency-Sequents (DDS). A ...

Add a description, image, and links to the existential-quantifier topic page so that developers can more easily learn about it.

Abstract: We prove the finite homomorphism preservation theorem: a first-order formula is preserved under homomorphisms on finite structures iff it is equivalent in the finite to an existential ...