The provenance of Usui's system is obscure, little independent documentation exists as to his influences. There are superficial resemblances to Chinese Taoist and Buddhist philosophies in the Reiki symbol terminology. Reiki however fails the standard test of whether a teaching is Buddhist or not; that of the three "Dharma Seals" or the "Three marks of existence". This doctrine states that any teaching or practice that does not extol these three core ideas cannot be said to be a Buddhist teaching, and Reiki does not.

Reiki may however be said to be a Buddhist art in the way that karate-dō or shiatsu is a Buddhist art without being a Buddhist practice. Similarly, the majority of Taoists would deny that Reiki was a Taoist art. The words used in these symbols show that their creator was exposed to these ideas. Whether or not Reiki was entirely spiritually received, rediscovered (as claimed), fabricated, or patched together by Usui and his followers from disparate influences, can only be guessed at due to lack of sufficient documentation.