Keightley is regarded as an early practitioner in England of the Brothers Grimm's approach to the study of myth and folklore, exploring the parallels between the myth of a nation to the religions and mythology of other regions. Thus Keightley began by attempting to trace fairy myth to Gothic and Teutonic roots, as the Grimms had done for elves. Keightley, like the Grimms, eventually reached the conclusion that it was implausible to trace a myth to an ultimate single source, and that parallel myths can be explained by the "Enlightenment idea that human nature is uniform," and similar experiences and responses are shared across mankind.