Chapter I elucidates Tolkien’s puzzling claim that The Lord of the Rings should be primarily considered as “an essay in linguistic aesthetic”. It first analyses a passing reference to the “cats of Queen Berúthiel”, described by Tolkien as the only element in The Lord of the Rings “which does not actually exist in legends written before it was begun”. This example introduces a discussion of a typical pattern of composition of Tolkien’s works: this begins as an experience of purely aesthetic fascination for a linguistic entity, which is then expanded into a narrative item, and later developed into a full, meaningful tale, through a heuristic process of ‘sub-creative discovery’. The second part of the chapter investigates the theoretical implications of such an approach, reconstructing Tolkien’s perceptions on the value and heuristic potential of a ‘gratuitous’ aesthetic event, and especially of a linguistic one, given the ‘divine’ inspiration of language and its original expression of both wonder at and knowledge of created reality.