Descartes Shaman seems like a gratuitous philosophical name drop, until you realize that the philosopher Descartes is the creator of the idea that a person can to only truly know their own mind, which is the origin of Solipsism. The series' setting, however, provides a way to get around the trappings of Solipsist thought: GN Particles and quantum brainwaves, which allow people to connect their minds and experience another view point, confirming the existence of minds outside one's own.
The movie within a movie adaptation that dramatizes the work of Celestial Being is also an example when you think about it. In this dramatization, Alejandro Corner is made the main villain and the leader of the A-Laws, even though he was killed at the end of the first season, before the A-Laws even existed. This might make no sense except when you realize that making any reference in the movie to Innovator or the Innovades (the actual villains), would lead to a public backlash against the Innovades, which would cause problems since the ESF is making use of the re-purposed ones (although their existence may be secret anyway). It would also probably lead to a backlash against the emerging Innovator population since people would probably have a hard time discerning between Innovator (the organization) and Innovators (the stage of human development). Alejandro then makes the perfect fall guy for the evils committed by the A-Laws.
At first glance, the film appears to forget or ignore the very real possibility that the increase in the numbers of Innovators and public knowledge of Innovades would likely lead to a world-shattering conflict, similar to the one between Coordinators and Naturals in Gundam SEED. However, it makes sense in the 00 universe, where there would be the very real fear that any sort of large-scale conflict would cause Celestial Being to begin their armed interventions again.
It is also not completely forgotten, being brought up near the beginning when the ELS start targeting the burgeoning Innovators.
It's also explained at the start that after the crimes of the A-LAWS became public, it caused a huge backlash against military buildup in global scale, making everybody equally afraid of the possibility of war. This probably played a large part in avoiding large scale conflict, and the ELS ended up unifying mankind even further.
One of the sidestories makes reference to an anti-Innovator and anti-ELS war that happens sometime after the movie.
Fridge Horror on that: Whatever happened to Sumeragi, Lockon II/Lyle, Allelujah/Hallelujah, Soma/Marie, the Vashtis, Lasse, Feldt, Kati, Patrick, et al., after 50 years? Simple, they could have died in that conflict.
The ELS sparked fridge brilliance within the timeline, an explanation to some of the alternative universe Gundams (Namely the Phoenix and it's research ability to reverse engineer everything). The ELS are responsible for the creation of the database within Phoenix. Until Ribbons ruined everything, that is.