Western civilization had a bit of a head start from the middle eastern and far eastern civilizations because so many were such a small area. Even though china had a lot of people 600 years ago when Europeans started spreading through the world, it wasn't anywhere as close to the amount of people in such a small area as Europe. As far as I'm concerned, western civilization is declining eastern civilization isn't doing amazing. All civilizations across the world are changing. We are becoming global and I wouldn't be surprised one bit if any 500 more years there are no more different civilizations on Earth and we are all just one civilization. By then, I think we will probably be on other planets and hell maybe some of those planets' inhabitants will start diversing and forming their own ways and civilizations. Just like a circle, same stuff over and over...