I grew up at a Catholic school. Now that I’m in college I’m taking a world religions class, and have to write a paper on the pros of monotheism- socially & physiologically.
There are no cons regarding monotheism. Philosophically, it is impossible to have more than one god—if that god is considered omnipotent, all knowing and perfect in every way. To even have two gods is to have no god. Each would lack that which distinguishes the other from it and therefore would be lacking in some way.
Some religions have minor gods that are called gods, but are so anthropomorphic that they simply mimic human behavior and actually resemble glorified creatures and not gods at all.
The sciences of sociology and physiology simply to not have the tools to study religion in anything but a superficial way.
See the following article from the Old Catholic Encyclopedia and check related items such as sociology, philosophy and theology.
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