(What follows is post 6 of 11 exploring the mystery of Tom Bombadil)
A Way Forward?
The first reason is rather simple; Tolkien's world is a thorough world that has histories upon histories, family trees and extensive explanations of the origins of various races and species. Tom though does not. It would be strange for Tom not to have a pre-planned origin and species even though Tolkien does not explicitly mention it. Tolkien stated that he was obsessed with making a consistent world, though he acknowledged that he often over-looked things by mistake. This reality is evidenced by the changes Tom went through to be included in Middle Earth. Tom originally appeared in a poem titled, The Adventures of Tom Bombadil, which was written before The Lord of the Rings, but Tolkien decided to include Tom in Middle Earth but not without some changes. Tolkien writes, "There have been a number of minor changes made at various times in the process of assimilating Tom B. to the Lord of the Rings world" (Tolkien's Letters, #240, pg. 318). This was in reference to his physical appearance. Originally Tom had a peacock feather in his hat but since Middle Earth did not have peacocks Tolkien changed this minor detail in order to assimilate Tom to Middle Earth. No one besides Tolkien of course would have ever known that peacocks don't exist in Middle Earth. But this shows us that in putting Tom into Middle Earth Tolkien strove for Tom to be consistent with it even in the minor details. So one may deduce that Tom's origins also should be consistent with Tolkien's creation.
The second reason is this, Tolkien goes out of his way to have Frodo ask several times who or what Tom is. It is clear that Tolkien himself had given much thought to the question of Tom’s origin. The question is even alluded to in the Council of Elrond and again in the Treason of Isengard. Tolkien was very much interested in who and what Tom was. Tolkien has much to say about Tom in his actions, character, and the questions others ask of him. Tom though is no mistake and he is intentionally a mystery but let us consider Tolkien's own words, "every part (of LoTR) has been written many times. Hardly a word in its 600,000 or more has been unconsidered. And the placing, size, style, and contribution to the whole of all the features, incidents, and chapters has been laboriously pondered" (Tolkien's Letters, #130, pg. 160). In other words, Tolkien was very intentional with his writing and he laboriously pondered everything he wrote over and over again. So, when the topic of who/what Tom is, comes up in no fewer than two occasions, we can be sure that Tolkien himself has thought long and hard about the answer to the question. So the question is not, “Is this possible” but rather, “How do we proceed in talking about Tom Bombadil in light of what Tolkien has chosen revealed to us?”
In letter number 144 Tolkien refers to Tom Bombadil as an "enigma" (Tolkien's Letters, pg. 174). It is precisely the reality that Tom is an Enigma that the explanations of him as a Valar, Maiar, and to a lesser degree a forest/middle earth spirit simply cannot do justice to Tom's status as an utterly unique creature in Middle Earth. Since Tom is an enigma, we should hesitate putting him in any category that is not one-of-a-kind. For example, the Maiar and Valar theories would not explain Tom as an enigma because they would make him far too common of a creature, one of many. The answer is too common for the great mystery which Tolkien wrote into the Lord of the Rings. Nor do these explanations explain many of the truths we know about him (eldest, reaction to the ring, Gandalf's words, and not having the power to resist Sauron). So it seems this enigma should be viewed in light of some of the other mysteries Tolkien writes about.
So going forward any theory formulated must take for account the enigma of Tom’s character. Tom is one of kind. Also, any theory must have textual warrant and grounding. Finally, any theory must be able to account for the very fiber of who Tom is and how he acts as revealed to us by Tolkien in the Fellowship of the Ring. After that, the theory must be examined by the three questions that all theories must be able to answer. At the conclusion of this process it will become clear that my theory has both textual warrant and grounding, it reaches to the very core of how Tom is portrayed, and it can better answer the big three questions than any of the other major theories and it does so with much less baggage. With that in mind it is time for my theory to be fleshed out, and that is Tom is the incarnated spirit of the Music of the Ainur.
Continues here: Tom as the Music