I have some questions about the study of logical reasoning and arguments.
Is it true that no two false sentences are logically equivalent? For example, "A square has 5 sides" and "I have one biological parent". I could not think of counterexamples to this.
Also, would every inconsistent set of sentences (that is to say, sentences that contradict each other) includes a logically false sentence in SL?
Lastly, can a valid argument with a false conclusion have true premises? I'm almost certain that this one is plausible since a valid argument does not require the truth of the conclusion.