Why did the ancient Egyptians believe in an orderly universe and Mesopotamia believe in angry pagan gods?

Answer 1

The people of Mesopotamia did not think that their gods were "angry". Nor did they consider their gods "pagan", because that is something that only Christians say about all gods that are not Christian. And Christianity was at that point still over 3,000 years away.

The Mesopotamians knew some 2,000 gods in total, mainly because every city had its own set of gods. These gods were venerated as protectors and as sponsors of trades, travel, war and art and basically were 'invented' as an explanation of the many things that people simply did not understand then, like 'what or who makes corn grow' and 'what or who causes the seas to be calm or wild' or 'what or who makes the sun rise every morning'. You venerated these gods so that they would keep you from harm or made you prosper in your life.

The ancient Egyptians believed in an orderly universe because they believed that their gods dutifully fulfilled certain tasks like making the sun rise and go down every day and because the steady yearly rhythm of the Nile inundations - so vital for their livelihood and prosperity - gave them a sense that there was an orderly rhythm in all other things as well.