I love stories; I love reading; I love thinking about things. One of the things I love thinking about is literacy. What is literacy? Are only those societies that have access to the written word literate?
Regarding the first question, I think literacy isn't so much about being able to read and write per se than being able to process and construct narrative around experience, about being able to derive insight and life lessons from experience. In this respect, the answer to the second question would be a negative. Stories aren't script and letters; the narrative is more than the words that express it: it is about being human.
All human cultures are literate. And it is only prejudice and bigotry that would suggest otherwise. Stupidity (ie, "illiteracy" as ignorance) is a symptom of gross negligence or an active policy of a ruling class. There are no "stupid" human cultures/civilizations in the prestine other than decadent, jaded ones on their way down.
Thinking about the Star Trek series and its various spin-offs, it seems that only the Picard character is ever seen with a book; there are also no textual symbols on the keyboards, walls or anywhere in the ships, just buttons or multi-coloured layouts. Even supposedly deep mathematical concepts are usually displayed as geometric shapes. If there is any semblance of text in a Star Trek episode it usually serves a decorative role - much like Chinese or Arabic calligraphy - usually connoting an ancient, dead alien culture. Whether this absence is an accidental oversight or by design...
I know many highly intelligent Inuit who do not read or write at all. Many of the characters in the classics (which I strongly suspect are based on actual social experiences of the authors) aren't able to read and write but are highly literate and eloquent, and very human. Even little children are capable of such insight, though in a haphazard, inconsistent way. They are still finding their voice, and if not unduly disrupted in their natural development will grow up capable of literate expression as second nature, capable of original thought and insightful observation, capable of highly abstract and beautiful symbolism, capable of subtle irony, metaphor and simile all.
I don't think I'm intelligent because I can read and write. My intelligence, like any human intelligence, is not language specific but have to do with a deeper native sensitivity to the spirit of humanity. A deliberately cultivated aesthetic sensitivity of the natural pattern-recognition machine that is human being is the very definition of genius. We all see the same things, speak the same words, work the same symbols, but in the hands of a Da Vinci, Picasso, Goethe, Newton, Einstein, the first creator/perfector of the qajaq, iglu, amauti...
The narrative is key to inspiration, creativity, and great conversation. There is no consumer product call "literacy" or "education" that one may purchase for these can only arise as organically cultivated characteristics of our being.
My best friend is a real gabber and highly literate, and I tremendously enjoy our conversations; I usually come away seeing or thinking about things in a new way. Else I come away infuriated enough to see or think things anew.