User:Gleki/Existential import

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    1. Unrestricted variables.

De Morgan Laws require that we first declare some existential variable(s), e.g. **da**, **de**.

1. We require that each such variable can refer to absolutely anything 2. We also declare that referents of each such variable must exist in the universe of discourse (even if never talked about or needed), and the result of such declaration is to be called "presupposition". 3. We don't question the existence of references of such variables **da**, **de** because we declared such variables and with them the existence of their referents as we wished from the beginning.

Now we can apply de Morgan laws:

a. quantifiers, negation and their scope within a single bridi do _not_ change the truth value of **da**: referents of **da** are presupposed to exist no matter what. b. Instead quantifiers, negation and their scope change the truth value of the _bridi_ they are in.

    1. Restricted variables

Now we wish to use a restricted varibles, e.g. **di poi pavyseljirna ku'o**

It differs from the unrestricted one in that it filters from the universe of discouse only those referents of **di** that are unicorns. Other than that the universe of referents of such variable is still big enough, only that we each referent is a unicorn.

1. We require that each such variable can refer to absolutely any unicorn. 2. We also declare that referents of each such variable must exist in the universe of discourse (even if never talked about or needed), and the result of such declaration is to be called "presupposition". 3. We don't question the existence of references of such variable **di poi pavyseljirna ku'o**.

Now we can apply de Morgan laws:

Notice that de Morgan laws, quantifiers and negation didn't touch the philosophical problem of the existence of unicorns. The existence of unicorns in the universe of discourse is declared earlier than quantifiers and negation were used.

a. quantifiers, negation and their scope within a single bridi do _not_ change the truth value of **di poi pavyseljirna**: referents of **di poi pavyseljirna** are presupposed to exist no matter what. b. Instead quantifiers, negation and their scope change the truth value of the _bridi_ they are in.