Witchcraft, Oracles and Magic Among the Azande is one of social anthropology's most noted texts.
In this work E. E. Evans-Pritchard examines the witchcraft beliefs of the Azanade, a group of agricultural people in southern Sudan on the upper Nile.
One is that witchcraft can be seen as a safety valve, that releases potential harmful conflict into less damaging activities.
The other is that it can be seen as an attempt to explain a complex alien world in a society's own terms of reference.
Together these make for a practical solution that is consistent and rational.