Interpreted as truth-functional, “if A then B” is equivalent to “A→B” is equivalent to “~A ∨ B”. Which is true whenever A is false, regardless of its relation to B or lack thereof.
“If that piece of butter had been heated to 150°F, it would not have melted” can be read as “that piece of butter has not been heated to 150°F, or it did not melt, or both,” or “it is not the case that both that piece butter has melted and that piece of butter has been heated to 150°F.”
Can anyone explain why Goodman considers this statement to be true:
Hence `If that piece of butter had been heated to 150°F, it would not have melted.′ would also hold.
Interpreted as truth-functional, “if A then B” is equivalent to “A→B” is equivalent to “~A ∨ B”. Which is true whenever A is false, regardless of its relation to B or lack thereof.
“If that piece of butter had been heated to 150°F, it would not have melted” can be read as “that piece of butter has not been heated to 150°F, or it did not melt, or both,” or “it is not the case that both that piece butter has melted and that piece of butter has been heated to 150°F.”