If you’ve ever considered drawing up a list of the most debased words, allow me to nominate radical. If you call someone a “radical thinker,” for instance, a great many listeners might assume you mean something along the lines of “cool thinker.” While we do tend to find thinkers cool here at Open Culture, more interesting usages exist. Some interpret the meaning of “radical thinker” as closer to “thinker of very different thoughts than everyone else,” and hit closer to the mark though they may, you can bet that someone else nearby has readied themselves to denounce the thinker in question as not nearly radical enough to qualify for the label. Like any complex word, phrase, or other element of language, we may have to define radical by looking at examples. Luckily, the Guardian and Verso Books have put together Radical Thinkers, a series of three-minute videos profiling exactly those.