Editing Sidanius Pratto 1999 (section)

====The Trimorphic Structure of Group-Based Social Hierarchy====
*Pierre van den Berghe’s three stratification systems:
**'''Age system''': the older have power over the younger. Interesting in that people move through all levels of power in this system if they live full lives (identity flexible).
**'''Gender system''': men have power over women (patriarchy). Authors conceptualized gender as fixed.
**'''Arbitrary-set system''': structures of power based on other socially constructed identities
***Authors argue this system has a high degree of flexibility and “arbitrariness” because the identities are socially constructed and depend on context.
**Argue that this system results in the most violence and oppression.
**Argue that this system is not found within hunter-gatherer societies, unlike the other two systems (PD: I feel like there are some alternative explanations worth considering.). '''You need economic surplus to produce an arbitrary-set system. It will arise where economic conditions allow.''' 
*'''Every attempt to abolish an arbitrary-set system has failed.''' (PD: has any attempt to overthrow the other two types succeeded either?).