ExistsLink

A Link representing existential quantification, in the basic sense of existential quantification.

So, for example: ∃x((x is human) and (x eats dirt)) is written as:

ExistsLink
  VariableNode $X
  AndLink
       InheritanceLink $X human
       EvaluationLink
            eats
            ListLink $X dirt

Note that PLN has some special math for handling the uncertain truth values of existential quantifiers (which is not fully represented in the PLN codebase as of March 2013).

ExistsLink is a subtype of LambdaLink.

ExistsLink is the declarative form of PresentLink. See the link comparison chart for further discussion.