Freud assumes that the reason for the invention of monotheism is because Egypt expanded into other nations and needed something universal. But monotheism nearly destroyed Egypt, so soon after its conquests. If Ikhnaton didn't believe it, why did he force it to his danger and detriment? The reaction was very strong, as you'd expect. A "strategic" genesis of monotheism makes no sense, with the way the events played out. If that was the intention, you really could call it a neurosis, but if it rose out of a sincere belief, and a powerful aversion to magic and the religion of Egypt, that makes a lot more sense. Really a fascinating read, have a go if you haven't.
If there's a God, monotheism is the most important development in history; if not, then the scientific method is. If there was a God, maybe he would tie everything together so that we could figure it out. Well, that's what happened, Francis Bacon's life is perfectly according to the hero-archetype Freud talks about in the beginning of the book. Royal birth attended with grave difficulties, adoption by those of a lesser station, fears that the child will be a danger to the state, and the child growing to be critical of the father. Really astounding stuff.