Im quite interested in some of the replies here, having thought it was widely accepted that Augustus et al had managed to put a system in place that fixed many of the problems inherent with the Roman "republican" system. Obviously that view is still in dispute with many people.

I have to say though that an empire that was doomed 20+ generations before its actual collapse has some pretty impressive longetivity. Few other empires have even lasted so long from start to finish.

Among the more interesting theories that I have heard for the end of the empire was the massive increase in the number of men becoming monks, leading to decline in population etc. This theory is based on the fact that at one point apparently one third of all men in Egypt had got the weird haircut and all that went with it. Not sure how much I believe it however...

One thing to note is the Roman "virtue" of looking back in awe of their superior ancestors. This to me is a sure sign of a society in decline. Roman authors
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almost
unanimously look back at (for them) historical times as better than where they were currently living at. This is not a healthy habit, especially as it was often not true. Debate exists over the reasons for this attitude, whether it was simply guilt, or far more complex feelings in regard to the fact their societal ancestors had conquered the world while they lived comparatively easy lives. Many Romans even idealised the lives of the "savages" they conquered, living much closer to the land and avoiding the corrupting influences of power and money.

This sort of attitdue was instrumental in forming the opinions quoted by Dol Guldor, and certainly an older, more judgemental and - dare I say it - more simplistic view of history compounded these views, condemning the Romans for destroying themselves. But when were these people writing, who were they actuall condemning?

Anyway, its an interesting topic that has been debated for 1500 years without resolution, and Im sure will be discussed for 1500 more - at least.