If there were one theme that explained the whole of the Demonsword Project, it would probably be engineering. The people of Draco developed a form of magic based on spirituality and centralized control; the people of Terra developed a form of holography based on computers and advanced physics. In other words, high-energy "magic" exists on both worlds, and in each case, it's because someone did the work to set up a system. Once the system was set up, they gathered users and information, and refined their techniques. In its own way, the Third Age represents a reboot of the two sides, allowing the collected knowledge to come together as one--although the costs were such that no-one would have done it on purpose.
However, when they do come together, it becomes clear to those who grow up in such times that they aren't two conflicting ideas. What, after all, is the difference between a technological scanner that reads your thoughts by algorithm, and a more naturally grown spiritual entity that learns to read human thoughts by experience? If they both perform the same act in the end, with the same level of control, were they ever really something separate to begin with?
However, it seems in the world we live in that mind and technology, spirituality and computation are discrete things. Call it left- and right-brain, if you will; art and logic, religion and science; or in DSP terms, "Mystic and Chaos". The Mystic side--those who gain power by trusting in the spiritual side of things--learn to do a great deal by trusting powers within them, by communicating with them, and by forming bonds. The Chaos side--the term being taken from Chaos Theory, a branch of advanced math--trust in knowledge, logic, and design. The Chaos side, however, will often fear the Mystic; for trust often means a hands-off approach, one where you never truly know your tools, but can only have faith. The Mystics, in response, will often fear those of Chaos, who never develop empathy, and who never communicate with their heart or soul; how can one come to trust those who forever shut themselves off from you?
Both sides have legitimate fears, and for those who have only ever known half the equation, it can be difficult to switch. However, the DSP also has one additional philosophical point to make, and one which I strongly believe in. It is a concept that the people of Draco call "Void;" it is an element associated with clarity, sensing, and divination. However, its powers are not innate; they are a combination of the other six elements, a combination that must be carefully balanced.
The philosophy of the Void is this: If you are predisposed to walk down any path, or are afraid to walk down any path, there will come a time when you aren't prepared to do what you have to. Indeed, to a Voidling, the sensory ability of that element is simply senses born of the other six elements, all combined into one. Knowing the boundaries of each, keeping them separate, and understanding their relations, allows you to see a great deal more than anyone who can only see a few elements.
It is a strong philosophy in other ways, and that leads me into the last theme of the Demonsword Project, the six elements. They aren't perfect, and in fact I can't say for certain they'll be arranged the same way when the project is finished and ready for launch as they are right now. They're a complex mess of philosophy and associations, but having created them, I respect the balance they represent. I'm sure it's too highfalutin (or crazy) for most people to consider a real philosophy, but I do. The elemental system of the Demonsword Project has been a major factor in how fun I find the project to work on, and as such, it's part of the reason I've kept going at it as long as I have. Even if it's changed, tweaked, or screwed with, I suspect it will continue to exist in some form for as long as the Project exists.