Now that is grim and fatalistic. @w@
Don't worry about getting too philosophical- an ancient war of ideas battling it out for supremacy is the beating heart of DA.
Order versus Chaos, Obedience versus Free Will. These conflicts form the foundation of everything, and it's all tied together.
That said, I don't agree. The fundamental nature of the world (our world as well as Thedas) is indeterminate. It's built into the very fabric of reality at the most fundamental level in a physics sense, which finds echoes in Thedas in the nature of the Fade and Reality. From a certain perspective, the fade is our physics, writ large. It embodies fundamental principles and gives them a physical, observable nature that allows us to explore them directly.
My background is cog sci, not physics, so this is going to miss subtleties others would spot and appreciate, but think about the fade for a moment as the ultimate indeterminate state of being. It is the particle in Schrodinger's box, waiting for an observer to decide its state. Cole actually references this directly in one of his banters with Sera: "In the soft, thin places, spirits push with memories that didn't happen. Or did. Or might. Before the door is open. They could let the cat out, and it would always be alive."
This is the core nature of the fade, and the source of sentient beings' power within it. Their presence -their thoughts and feelings- directly shape the world around them in an immediate but impermanent way. "Change" in the fade, to drive home the point, is fundamentally an illusion. It isn't real.
The real world of Thedas works differently. It is slower. Heavier. A being can no longer shape the world with idle thought, they must act on that desire. In the real word, thoughts and beliefs must be followed by choice. By action. Or they do nothing. As Cole notes, "here is what can change." And though being forced to shape the world this way is slow and heavy, those changes stick. Even if opposing forces twist or reverse that change, it cannot be erased. The world does not return to its original state- a quick glance at history will tell you that. Every action -every choice made- has echoes that persist.
The Andrastean Chant is right in this: if there is a Maker, free will is his greatest gift. Choice grants power to all - not just mages - to change the world around them. That is why it is such a sacred, fundamental concept for Solas, and is the antithesis of what the Sun/Elgar'nan desires.
I...yikes. I need to stop before I start off on a tangent about Order and Chaos, free will, and how that balance relates to the Song- the gradient from single melody through complex harmonies to dissonance.
Anyway! Like I said, don't ever stop yourself from jumping into the philosophy. The game itself is prompting you to examine these things at every turn. Bioware wants us to think.