In fact, Ess explains how literacy leads to social stratification and social stratification and social hierarchies cause discrimination against women.

             The Incas, one of the richest and most complex societies in the Americas before European conquest, were largely preliterate. Lehrer notes, "The Incas built impressive roads, made developments in astronomy, and were at least the equals of 16th-century Europeans in many of the sciences." Most historians, anthropologists, and archaeologists believe that the Incas never developed a system of writing or an alphabet in spite of their immense cultural and scientific achievements, proving that literacy is not itself a significant factor in a society's or an individual's development. Literacy is certainly not an evolutionary step. Yet Lehrer states that many researchers are struggling to prove that the Incas did have a writing system-as if to prove so would elevate their status in the history books. Scholars simply "wonder at how a great empire existed without a writing system," as if they cannot accept that literacy is not essential to social success. Lehrer admits that if an Incan writing system were discovered it would "change the entire way in which they look at the empire.".

             Literacy is a culturally biased, value laden term. Moreover, literacy means different things to different people, and the UNESCO definition of literacy is only one among many. For example, the cutting-edge philosophy of memetics frames literacy in a novel way that can illuminate some of the different ways literacy is construed. "In preliterate societies, memes spread exclusively by direct demonstration or by word-of-mouth transmission," ("Memetics and Society"). An individual learns by observation or by receiving oral instruction: both methods are independent of written alphabets and may be superior in terms of skill acquisition, as no one could deny that direct instruction is superior to reading textbooks.