There is great irony in denying God as the ultimate Source of knowledge, for to claim knowledge that God does not exist, or that he is unknowable, is to assume his existence in the first place. Since God is the only viable explanation for knowledge, any argument brought against him must presuppose his existence. The folly of claiming to possess justified true beliefs while denying the existence of God may be likened to the folly of claiming to be a mother while denying the existence of children, or claiming to be a dentist while denying the existence of teeth.