Blackbeard was said to have the hobbies of studying history and his real world occupation would be an archeologist.
He probably knows more about the world than we think, maybe even Poneglyphs and the Will of D.
Knowing a lot of history, he can probably see patterns forming.
1-He believes in destiny and fate because of all the coincidences that happened to make society what it is today. This is why he doesn’t fear death and charges into battle even against opponents like Magellan, because he knows deep down that a stroke of luck will make everything turn out his way.
2-Dreams will never die. Francis Fukuyama once wrote a book in 1992 called the End of History stating that society’s troubles had all ended, which was proven later to be false. The era where people will stop dreaming of exploration and adventure never dies, which is apparent when reading history.
3- Blackbeard sees no World Government institution as truly legitimate because he knows all of them come from some force winning a battle of strength, so you shouldn’t care about the Government if you’re strong enough. They’re basically just the most succesful pirates in that area. Kong is just a Yonko to Blackbeard and the Marines are the Commanders. Imagine if Blackbeard puts out Wanted Posters on Government Officials. He would probably have just as many bounty hunters after them as there are bounty hunters after Pirates.
4-There’s no Justice or Evil in the world, only power and survival. Your happiness comes before everything else. Cuckoo birds, parasitoid wasps, kings, CEOs, all didn’t get where they are by caring about others. Blackbeard has only really killed people for his own personal gain and in self-defense, while Government officials like Rob Lucci and Akainu kill the defenseless and then justify it later on.
*Theory by Kusokuso69