Fiction in Middle Earth

[Sophia the Thunder Mistress]

A few thoughts. Hm, davem, are you talking about literary subcreation alone? or subcreation of all kinds? Because I think that makes a bit of a difference in the way you look at the subject.

I know the elves' "magic" has already been discussed, but their visual artistic creation was present too. An example being the Halls of Menegroth fashioned to resemble the gardens of Lorien, or the trees Brethil and Glingal of Gondolin, or the swan boats of the Teleri, the Gems of the Noldor, the architecture of Rivendell and Tirion...

Tolkien does say expressly that the elves are to function as subcreators in ME

"By the making of gems the sub-creative function of the Elves is chiefly symbolized..." Letter 131

That however, doesn't mean they are the only ones taking part in the act of subcreation. We also see the Valar as subcreators, as their thoughts in the great music are realized (the Ents, snow, etc.)
This seems to be a theme in Tolkein as well, the Creator realizes the subcreations of his people; it also appears in Leaf by Niggle.

I also wanted to point out, that most mythology is, as others have said well, organic, growing out of a people and a culture. Tolkien is, to my knowledge, the only one to try to "create" the kind of mythology he undertook. Other writers write fantasy, Tolkien writes translated history. If there's only one of him on the current Earth, why do we expect ME to be abounding with this sort of behavior? Only one Vala created Dwarves, only one Noldo created Silmarilli, only one man created myths (in the way that Tolkien did...). I for one, am not surprised that the myths of middle earth are organic rather than created.

-Sophia