The family emergency has been called off, but I'm not sure of where I was going with the business about the spirit-stuff.

The question is, how does one go from being tangibly invisible to being intangibly invisible? The Nazgul were wraiths, and without the black robes they wore when tracking down Frodo they had no "shape", as Gandalf put it. I take this to mean that they had no physical aspect which was tangible. They should have been able to pass through walls and all that stuff.

When Merry stabs the Lord of the Nazgul, his Barrow-blade breaks the spell that binds the Lord of the Nazgul's unseen sinews to his will. These unseen sinews may or may not be the "spirit-stuff" I was speculating about. But the passage implies the Lord of the Nazgul had the power to control these unseen sinews. Where could he get such power? Clearly, from his Ring (or directly from Sauron, but I propose it's the Ring). Does that mean Merry's sword need be as powerful as the Ring? Not necessarily. Binding the "spirit-stuff" in such a way that it didn't leave the world as it normally would should be only a small part of what the Ring was capable of doing.

Although the Nazgul were utterly enslaved to Sauron's will, they were still capable of acting independently. This means they were sort of super-brainwashed, incapable of conceiving of any plan or desire which would be contrary to their lord's purposes. But they nonetheless could still originate thoughts and ideas, even about themselves. Hence, it was necessary for them to control their unseen sinews.

The process of fading virtually reduces a physical body to nothing. But even in Tolkien things don't just happen irrationally. He must have envisioned the physical aspect of the body undergoing some sort of transformation. We can offer pseudo-scientific explanations for transformational processes, but the point we need to pursue is what the purpose of such transformations would be. And what effects they would have.

Where should the body "go", if it's no longer going to be part of the physical world? For an Elf this is a strange question. An Elf fades naturally and becomes a disembodied spirit. A Man doesn't do that, but his body decmposes once he stops living. I don't believe a faded body decomposes.

The transformation may something like a matter-to-energy transformation, but not "energy" as in plasma, electricity, the energy of things in motion. Rather, "energy" as in "spiritual power" or "raw spirit stuff". If I understand Tolkien's construction properly, that Ea has at least two aspects to it, a physical and a non-physical aspect, then the transformation of a body from the physical to the non-physical must work something like the conversion of matter to energy.

Hence, Ea loses nothing. There is conservation of Ea in the transformation, but the transformation changes the balance between the two aspects of Ea. One becomes larger and one becomes smaller (quantified, but not necessarily in measureable dimensions of size and distance). Or, to put it another way, think of liquid water and mist as two aspects of reality (the only two aspects). There are things which take shape in the liquid water and which somehow become mist. The overall amount of water is preserved, but the amount of liquid water diminishes while the amount of mist (gaseous water) increases.

I feel very much like a two-dimensional being trying to describe a three-dimensional universe. I don't believe Tolkien had a fourth dimension in mind, but rather two states for the three dimensions we perceive: a physical state and a non-physical state. The non-physical state is here, beside us, around us, within us. We can somehow transform ourselves (with the Rings of Power) into non-physical entities, but we cannot normally perceive the non-physical.

This seems to be what Tolkien refers to when Gandalf says that those who have dwelt in the Blessed Realm live in both worlds at the same time. The Valar and Maiar were not always self-incarnated, but they could have taught the Eldar to be sensitive to their dis-incarnated spirits (if they wanted to be sensed by the Incarnate) and to perceive much in the non-physical world. Hence, Glorfindel could probably see the Nazgul with a "spiritual vision" (an "other" vision, perhaps, as Sam saw with on Mount Doom -- but that is another ball of wax) but he may have had to exercise his will to do so.

I wonder if, when Frodo beheld Glorfindel in his wrath, Glorfindel hadn't actually faded a little so as to appear more visible in the wraith world? As one of the ReIncarnated, Glorfindel was (according to Tolkien in THE PEOPLES OF MIDDLE-EARTH) much more like one of the Maiar. He may indeed have obtained some ability to control which aspect of his existence was most pronounced, though not necessarily to the same degree as a Maia or Vala in their full power.
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