Wikipedia article on Dehumanization: http://en.wikipedia.org/wiki/Dehumanization
Description of Dehumanization: http://www.deathreference.com/Da-Em/Dehumanization.html
The psychologist who created the Stanford Prison Experiment talks about how we can do evil things to each other: http://lucifereffect.com/dehumanization.htm
Video of Police cutting up tents of homeless: http://www.youtube.com/watch?v=LrPdZmPB36U&feature=related
Homeless Evicted from Tent City in Sacramento: http://video.google.com/videoplay?docid=3583155434947566213&ei=-Di2SN7IKaSyqAOJn4C-DA&q=homeless&vt=lf
Hate crimes against the homeless—press conference: http://video.google.com/videoplay?docid=-234498057173364594&ei=SkW2SPOTAo3CqAO_gdHKDA&q=homeless