Question: The relationship between literacy and “truth”

Most especially inspired by the many complexities presented in the Goody and Watt article, I am wondering what the relationship is between literacy and truth.  This article purports that more literate societies are more individualized, more aware of history with regards to the present, and thereby more forced to examine issues, inconsistencies, and problems arising between the disparities created by these many overlapping relationships.  Does this also then assume that literate societies are better able to determine social, scientific, existential, or metaphysical truths?  Wouldn’t a society who was more focused on just the relevant present (illiterate) be better at discovering social truths?  Did the article section about Socrates/Plato/Aristotle convince us that oral tradition served to better determine existential or metaphysical truths?  What relationship, if any, is there between literacy and the determination of truths for a given society do you think?