The last episode of this show left me completely confused. I have some questions I hope someone can help me with.
1. Why did Proxy One create Vincent/Ergo?
2. Why did Vincent erase his memories?
3. When/why did Proxy One abandon Romdo?
4. Why did Proxy One not want Vincent to remember?
5. Why does Ergo Proxy kill other Proxies?
Hey, so from watching the show, this is my take on it. To start, Vincent obviously is in one way or another, a clone of Proxy one. He was created by merging Proxy One's cells with that of Monad, but instead of pregnancy, we got an artificial Proxy who we know as Vincent Law. Vincent has the same facial features as Proxy One, and he also possesses the same set of skills. He is everything that Proxy One was, but the reason for his creation has to do with Proxy One's infinite rage for the creators (who are the humans that left the earth thousands of years ago after making the earth's environment uninhabitable via the overabundance of methane gas or something along those lines.) when Proxy One first found out the reason for the proxies existence, which were to govern the earth by creating those domes that can hold the remaining human survivors that never left the earth, he also realized the irony in the proxies existences. In a sense, the proxies were the creators servants, because they did all the work to make the world hospitable again in time, but he also realized that once the proxies were to fulfill there duties, they would no longer be necessary in the new world. Proxy one realized that fact, and foresaw the inevitability that would be his and every other proxies demise. Because he learned of this possibility and fact, his anger towards the creator led him to abandon his domed city, and create Vincent. All proxies, as they are artificially designed by the creators, cannot resist the urge to fulfill the creators mission. In a sense, the anime delved deeply into what makes a human a human. Does a human being constitute a person, or can anything else with a sentient ability to think for themselves constitute a human being in the sense that they have free will and a soul to make rational ideas. That's also why the virus that infects the autoraves is called the cogito virus, because of what the word cogito means. The prayer scene with each infected autorave can also symbolize something that a human does. It shows a religious stand point in which we look up towards a higher being. This delved into whether an autorave ended up being constituted as a human even though they were robots. Anyhow, this also mean't that Proxy one hated the fact that just because he and every other proxy were created by the "creators," they would become obsolete and unnecessary after fulfilling the mission of watching over the earth and keeping the remaining survivors alive until the earth was hospitable again and when they would return. Having realized the irony of the proxies existence, he created Vincent, and devised everything to happen as it did in order to get revenge against the creator. Seeing as the Proxies would all have to die when the creators return, Ergo Proxy, both Proxy One and Vincent Law, who was in a sense his clone, couldn't resist the mission of destroying all the other Proxies, as they were the agents of death. The sole reason that Proxy One was created was to be the Ergo Proxy, who was the agent of death. His role was to annihilate all the other proxies when the time was right for the creators to return and because Vincent was Proxy One in that regards, he couldn't resist his impulse to kill them. Furthermore, it can be said that Vincent never really forgot, but rather never had those memories to begin with. He was put into a tough reality as it was, and he never truly questioned his past prior to the unveiling of all these events. It can also be argued that Proxy One simply schemed all the events to happen the way it did, so Vincent simply fulfilled his duties the way he was made to. In the end, because all Proxies are supposed to burn in the presence of sunlight, Proxy one was content with the simple fact that Vincent wouldn't burn like the rest as he different from all other proxies in that he was made from both monads and Proxy Ones cells. This was also Proxy One's way of revenge against the creators as it went against the desired destruction of all Proxies after the creators were to return.
Don't get me wrong though, i can be completely wrong too. This is my take on it. Hopefully this helped a bit though.