The Reflection Crack'd is a pretty important short story for EC fans. First of all it provides a link between the Fulgrim and Angel Exterminatus novels. Secondly, it firmly confirms that Fulgrim is now himself, and not a demon from the warp. Not to mention that it kills off my favorite HQ, Eidolon.
The story is also notable because Fulgrim shares some further insights with his legion with regard to the true nature of perfection. As previously established, Fulgrim does not seem to acknowledge a division between spirit and the sensate material world.
However the Reflection Crack'd takes things a step further. In essence, Fulgrim seems to imply that the material world has been infused with a desire to seek more complex forms, greater purpose and more opportunities. In other words it seeks to attain perfection through advanced development and diversity.
Here are some select quotes from Fulgrim's lips:
"Think of how one measures good and evil and you will see that what I am, what I am becoming, is a thing of perfect beauty. A thing of goodness."
"This universe began in simplicity, with an event of such rapid expansion that it cannot ever be measured. In the first fraction moments of its existence, the universe was a place of such staggering simplicity that we cannot even begin to imagine it. But over time, those simple elements began to cohere, to come together to ever more complex forms. Particles became atoms, and atoms became molecules until they grew in complexity to form the first stars. . ."
"None of this coming together is random. It is part of the universe's nature, its tendency towards complexity. . . all things are part of this cycle of building and coming together, from the lowliest organism to the highest functioning sentience. Given the right circumstances, everything will tend towards becoming something more beautiful, more perfect and more complex. This has been this way since the beginning of this universe's lifespan, and that nature is as inescapable as it is inevitable."
"If you accept that the universe is constantly moving towards its final state of perfect complexity, and that this is its inevitable destination, then anything that hinders this process must be defined as evil. By the that same logic, anything that promotes this ongoing journey is surely good. I am moving towards that perfect complexity, and by hindering my ascension you are acting in the cause of evil."
Surprisingly this mode of thinking has a long history with our own modern perspective. It is in essence a teleological argument. Science hypothesizes that out of the chemical building blocks of life, that the original single celled organisms arose. Those organisms grew more complex and achieved greater possibilities, becoming fish, then amphibians, then reptiles, then mammals, then humans capable to perceiving their own consciousness and building mighty cities and exploring space. Fulgrim in essence embodies and universalizes an evolutionary / intelligent design perspective.
The alternative is stasis, puritanical limitations and gradual decay. Somewhat like what 10,000 years of deterioration have done to the Imperium and the occupant of the Golden Throne.