After The End

What is a world that is only ruled by humans? A world where no god or demon is feared as the humans defeated them and finally become equal and more powerful than them?  A world where humans do not fear the unknown as the unknowns finally became known and the  great mysteries that haunted men for so many centuries finally became solved?  What will become the fate of humans after the unknown variables of the world ceased to exist?  Will humans finally learn to surpass their own limits and become the greatest creature in the cosmos or are we just humans no matter what we achieve  or who we defeat, we bring about our own destruction?   And finally when its all said and done, like a snake that eats its own tail cause of greed, the hand that will cause the end of humans is not that of a supreme being or an evil being but the hand of the humans themselves?  Are we truly our worst enemies?