https://maximummathematics.com/books/foundational-mathematics/logic/quantified-laws-of-logic/index.htmlWhat can we deduce from knowing that a universally quantified open statement is true? What can we deduce from knowing that an existentially quantified statement is true? How are universally quantified statements and existentially quantified statements related to each other? In this section, we dig deeper into quantifiers, and explore propositional logic involving them. A Simple Definition Just like with ordinary statements, we can ask whether two open statements are logically equivalent.Hugoen-US