In this age of extremes, this documentary exposes the scientific reasons why humans tend to be irrational when it comes to their personal beliefs. Look at the comments here for example and you will see what I mean.
The cinematography is very well done, with interesting shots and high quality digital enhancements of old videos.
The main plot throughout the series is the weakness of the humans mind to stand up and refuse the group think (whatever this may be) and to think for oneself and see if it is really what the group says that it is. With many examples given (congo, experiments in psychology and much more) there is no doubt that this aspect is one of the most important things we need to overcome if we are going to live in a fair world.
The series makes it very graphic and gritty with very extreme videos/images (real dead people, mass graves, blood etc.) to get the point across that we need to change if we are to survive as a species.
I would recommend this to anyone who is wondering (like the title says), Why Humans Hate, and want to know what to do about it.
If it weren't for the very graphical scenes I would even recommend it be viewed by teens in high school so they can be prepared and know what to look out for in group think ad other thinking fallacies.