I occasionally encounter people on gaming forums who talk about “hardcore gamers” as if there’s some kind of accepted definition of the term. You know: “hardcore gamers are gamers who play more than 25 hours a day and who only drink Red Bull intravenously” or something like that. The problem with such ‘definitions’ is that they rely heavily on vague concepts, which means it’s very easy to play with your interlocutor’s head by recursively asking them for definitions, complaining that their terminology is imprecise. That rhetorical technique is the real reason they killed Socrates.