Logic and Quantifiers

A valid argument form guarantees the conclusion whenever the premises are true. Learn the classic valid forms and the common traps.

Equivalent statements always have the same truth value. Use standard laws like **De Morgan**, **implication**, and **double negation** to rewrite expressions cleanly.

When a statement has **more than one quantifier**, the order matters. Negating the statement flips each quantifier and negates the predicate.

Quantifiers tell you whether a statement is about **all** objects or about **at least one** object.

Truth tables let you compare two statements **row by row**. Two statements are logically equivalent when they match on **every** row.