70 is retarded, 100 is average, that is a 30 point difference. 100 is average, 130 is gifted; that is also a 30 point difference. (…) The same distance in intelligence that this average child is away from his mentally retarded peers is also the distance a gifted child is away from his normal peers. To put it bluntly, in case you’re still not getting it, a gifted person living in an average world is a person surrounded by those he or she will perceive as mentally retarded. Insert the screams of existential horror here.

http://www.alifeofthemind.com/2011/02/13/mensa-iq-the-30-point-gap-and-the-outsiders/