Lots of our visual design students investigate why certain campaigns go viral, and others languish. Turns out what works online is what's always worked.

The question predates Berger’s interest in it by centuries. In 350 B.C., Aristotle was already wondering what could make content—in his case, a speech—persuasive and memorable, so that its ideas would pass from person to person. The answer, he argued, was three principles: ethos, pathos, and logos. Content should have an ethical appeal, an emotional appeal, or a logical appeal. A rhetorician strong on all three was likely to leave behind a persuaded audience. Replace rhetorician with online content creator, and Aristotle’s insights seem entirely modern. Ethics, emotion, logic—it’s credible and worthy, it appeals to me, it makes sense. If you look at the last few links you shared on your Facebook page or Twitter stream, or the last article you e-mailed or recommended to a friend, chances are good that they’ll fit into those categories.