One of the major causes for great social change in Europe in the 18th century was the role of literacy. While measuring actual levels of literacy and its meaning are contested by historians, there is no doubt that literacy reached levels that no longer included the upper class institutions, as evidenced by the numerous pamphlets spreading through France before the storming of the Bastille or the popularity of Thomas Paine's Common Sense. More people read, learned what was going on around them, and made judgements to change the course of history based around the persuasion of language.
However, literacy has always required a two way street of both education and erudition along with understanding of an audience's own proclivities. Write with obscure language and alienate your audience. Write without strong grammar or spelling and lose the other side. Literacy as both a skill of reading and writing takes time to hone and consider, and as a species, we've had numerous millennia to try and reach a state where words can perform actions.
In our myth of cinema's founding, media literacy was not innate. People ran from the train as it arrived in the station. Hungarian film theorist Béla Balázs has remarked upon audiences members confused where the rest of the body of a woman was while her face was in close-up. These problems, however, quickly faded away. We all quickly understood what it meant to watch something, how editing worked, and most importantly, that often the images presented to us contained some sort of reality equivalent, the indexical.
This was a hyperbolic movement of the 20th century, much faster and expedient that textual literacy. The moving image as a democratic force soon took hold as the medium to communicate to masses, be it immigrant families in the Lower East Side, abused plantations workers in Brazil watching on a cloth sheet, or simply now streaming on the Internet. Maybe not everyone can read, but we sure as hell can understand the basics of a movie.
With that rapid expansion, however, the implications of the possibilities by those who were media literate became frighteningly unchecked. We've come to understand what we can show mass audiences and all of its potentials, but in many ways, the speed of media literacy in the 20th and 21st century has not allowed us to look further into why and how we are watching things. And thus, a person can now film himself willingly taking the life of two individuals, and then later his own, and gain an audience to watch his horrific acts. He has his reasons for shooting the video, as we have our reasons for watching. But perhaps we aren't as media literate as we thought. Perhaps we need to consider stronger implications of our democratizing technology, and more importantly, the low bar that media literacy allows for basic comprehension but not human comprehension. Media literacy can cause historical change, but more and more, its only aim is perhaps simply appealing to base emotions, abusing its indexical power to confuse us from reality instead of growing a larger social consciousness. Roger Ebert called cinema a great empathy device. I'm not sure I believe that anymore.