The Logic Resource Center

Public Alpha

Systems

Public Alpha

Existential Introduction

Classically known as Existential Generalization, this principle says that you can prove a predicate holds of a specific thing, then you can infer that there is something of which that same predicate is true.

Constants: ∃
Systems: LRC_F OLI The Logic Book LRC LRC_P LRC_O

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Existential Introduction

i.

ϕ(α/γ)

ii.

(∃γ)ϕ

∃I: i

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Preview shown for the Point And Click derivation type in the The Logic Book system