Ok I'm sure you've all seen this topic somewhere before, well here it is again.
I myself believe Mew came first, and I have a theory that could explain why theres only one Arceus and more than one mew, and why Arceus is stronger than mew.
First off I think that Mew(The First Mew) created himself, and WAS a god, in a void without Time or Space. Mew then created Arceus who then created the universe,Space and Time.(Mew still outside of space time, so Arceus was the first in the universe and its origin since he made it). Then Arceus made the other gods, and they created the the Matter and Energy in the universe. With the universe complete Mew left his dimension and entered the universe, and then he created all other life.(I don't know what you might think but i believe there are more worlds with Pokemon other than the one we know). Then Mew abandoned his godly form and splitting himself and his power (the reason Arceus is stronger) into many mews and sending them to the different planets with life to act as guardians on the separate planets(each one having the ability to become any Pokemon and use all their powers at anytime and I believe they still retained the power to create Pokemon).With Mew no longer being a god Arceus became the most powerful Pokemon and the god of all Pokemon.
Ok this is my theory and I'll like to here your input on what you think about it. I would also like to know who you think came first Mew or Arceus and what your theory's are.