We all know at least one of these guys. Or maybe it's a girl. Or, fuck it, dog. Smartasses come in all shapes and sizes, much like regular ones. It's just that only one of those can be corrected with an old-fashioned punting.
Dogs can be smug assholes too. Don't get me started.
The weird thing about the annoying know-it-all personality type is that they seem to be everywhere. The reason behind this is simple: He literally is everyone. We all carry elements of Chad within us, and every once in a while that fucker surfaces and starts whipping assumed knowledge around like crotches in that Dick Slang video. With the slightest of modifications, it's the default mode of annoying brats and teenagers everywhere, the prevailing mindset of roughly 99.99 percent of all Internet forums, and, of course, the mindset behind that tiny voice in your head that wants to mock and yell at other people when they don't use the gun you prefer to shoot faces off in your online video game.
Unfortunately, you can never teach yourself to un-besserwisser. Not really. Even the best of us aren't above occasional, annoying know-it-allery. Grab a Bible and take a vodka shot every time Jesus, by default a template of a perfect human being, delivers a condescending "You know nothing"-style line to someone. I guarantee you'll be drunk well before Golgotha.