Final answer:
In propositional logic, existential quantification is typically considered modally inclusive, allowing for the coexistence of multiple entities within the same reality. Existentialists like Jean-Paul Sartre identify two fundamental types of beings that share reality, while post-modernists entertain the idea of multiple realities. Thus, existential quantification supports the coexistence of diversely existing entities.
Step-by-step explanation:
The question 'Is existential quantification in PL exclusive or modally inclusive of other existential quantifications in the same discourse universe?' explores the nature of reality in the context of propositional logic (PL) and existential quantification. In PL, existential quantification is not exclusive but instead, it is typically considered modally inclusive. This means that within a given discourse universe, the existence of one entity does not preclude the existence of others.
Existentialists such as Jean-Paul Sartre proposed two types of beings: being-for-itself (conscious and free) and being-in-itself (non-conscious). These beings coexist within the same reality. Post-modernist perspectives suggest the coexistence of multiple realities, modally inclusive, but existentialists focus on the concrete existence of humans and objects, rather than abstract realities.
The notion that there can be more than one total reality is a profound ontological question. Considering the arguments from existentialists and post-modernists, it seems that while personal perspectives vary widely, the existential quantification in PL suggests inclusivity of existences, rather than exclusivity.