Law and Science are supreme at this time. I believe by looking at a Birth of a Nation through a Swales and Mirrabeli lens allows you to see how people interpret the images they see. For example, Black people do not have rights, Black people are inferior scientifically and seeing it depicted in such a way they can now see why. I think this was dangerous because it reinforced these ideas. It also built resentment from people who were already upset about the disassembly of the confederate.
In the first scrub that we are supposed to complete regarding costumes, iris, typage, etc I believe that Griffith wishes to victimize the south. The woman is shown in rags hopeless with just her children as the camera pans over and uses the iris effect to show the union taking over with no regard to their lives. It shows commoners in chaos being attacked by the soldiers.
In the next scrub we see a master and slave depicted where he is seemingly very compassionate and she throws tantrums and is nasty unprovoked. She seems to have fair treatment from her master but she appears to be ungrateful.
This was a bit harder to figure out without words but it seems that they believed the mixed race people were dangerous. The same woman I believed to be a slave seemed crazed and a bit looney. This seems to be what they wanted to convey as what happens to freed people.
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