How do you know the men who were inspired to write for the bible had direct communication with a God?

You know for a fact that they didn't. If they had been inspired and instructed by an amighty "god", they would not have written such a cobbled up, contradictory, patently untue book. Would a "god" who created the earth think it was flat? That the sun revolved around the earth? That a bat is a bird? That a ridiculous wooden boat could hold pairs of all the animals for nearly a year? There is no end to the idiocy of it all.