From wikipedia
The bottom 25% have no net wealth
the middle 50% (25-75) have 13% of America's wealth
While the top 25% control 87%
From another source, the top 10% control 70% of the wealth while only paying 55% (from your figures) while those holding 30% of the wealth pay 45%
Go through a list of major scientific figures from the dark ages. They rapidly accelerate till around 1100AD followed by a sharp falloff. Science had all but stopped centuries (1300AD) before the renaissance began. Can't find anything better put together googling @ the moment but - this should give you an idea
Also read up on the mutazilah who dominated the scientific (scholar) community until Ghazali gained popularity resulting in them dying out (including many being killed outright) and the asherite (conservative) school attaining dominance
An authority is a person who can tell you more about something than you really care to know.