Refers to George Carlin, a comedian from 1960s-2000s. Carlin was prolific in his (usually profane) observations and ridicule of societal norms.
The shared beliefs of George Carlin (1937-2008), one of the greatest human minds that ever lived. Carlin taught us that Republicans/Conservatives are full of shit, kids today are largely flawed, God doesn't exist and those who believe in most religion are assholes who kill people for no reason (His words, not mine.), and people in general are scared, weak, evil, manipulative, callous sacks of shit who sit around playing with their pricks until they die, and other such thoughts.
Churchgoer: Hey, I'm going to church, wanna come?
Carlinist: No thank you, I believe in Carlinism, now if you'll excuse me, I'm gonna go jack off.