"If it was a statement you made just to make a point, but do not believe in (also known as a lie), then that is of less value than statements made by persons who believe they are telling the truth."

But you can't assess that value because you don't know whether I'm telling a lie or whether I believe I'm telling the truth. The thing is, there are no fairies at the bottom of the garden. Whether I'm being genuine or whether I'm lying makes no difference to that rather obstinate fact. So both statements are intrinsically equally valueless.