Meanwhile, when you read the Silmarillion (and go back and read The Hobbit in its light), you discover that there were three great kindreds of Elves who made the great journey from their place of origin to the Blessed Realm in the West: the Vanyar, the Noldor, and the Lindar (or Teleri). In going into all the tribes of Elves, Tolkien seems to be straightening out the confusion of old Jacob Grimm, whose inquiry into the nature of elves in Germanic legend could not find a satisfying conclusion. At least, so says Tom Shippey, and he publishes the evidence for us. So that makes sense.
But what, then, shall we make of the three Houses of the Edain, the Men called "Elf-friends" in the First Age, who became the Numenoreans, and created the realms of Arnor and Gondor after Numenor's Downfall? Does no one else not notice this motif re-occuring? Three tribes of Hobbits. Three kindreds of Eldar. Three houses of the Edain. The pattern is certainly there, it's not a mirage. "Three times is a threat," said Gollum, but there is no threat here. But is there a lack of imagination? Does the evidence run that way on its own, or is this the only pattern Tolkien knew? Is this a defect or a mere duplification (or triplification, as it were)?
We wonders, aye, we wonders.