The Secret Doctrine, the Synthesis of Science, Religion and Philosophy, is a pseudoscientific esoteric book as two volumes in 1888 written by Helena Blavatsky.

[1][2][3][4] In Volume One, Blavatsky details her interpretation of the origin and evolution of the universe itself, in terms derived from the Hindu concept of cyclical development.

[5] These central points are as follows: The second half of the book describes the origins of humanity through an account of "Root Races" said to date back millions of years.

[citation needed] "The real line of evolution differs from the Darwinian, and the two systems are irreconcilable," according to Blavatsky, "except when the latter is divorced from the dogma of 'Natural Selection'."

These basic ideas are few in number, and on their clear apprehension depends the understanding of all that follows…[7]The first proposition is that there is one underlying, unconditioned, indivisible Truth, variously called "the Absolute", "the Unknown Root", "the One Reality", etc.

[d] Related to the above is the third proposition: "The fundamental identity of all Souls with the Universal Over-Soul... and the obligatory pilgrimage for every Soul—a spark of the former—through the Cycle of Incarnation (or 'Necessity') in accordance with Cyclic and Karmic law, during the whole term."

[14] In the second volume of The Secret Doctrine, dedicated to anthropogenesis, Blavatsky presents a theory of the gradual evolution of physical humanity over a timespan of millions of years.

She also prophesies of the destruction of the racial "failures of nature" as the "higher race" ascends: In The Secret Doctrine, Blavatsky states: "Verily mankind is 'of one blood,' but not of the same essence."

Historian Ronald H. Fritze has written that The Secret Doctrine presents a "series of far-fetched ideas unsupported by any reliable historical or scientific research.

She claimed to have received her information during trances in which the Masters of Mahatmas of Tibet communicated with her and allowed her to read from the ancient Book of Dzyan.

[16][17] L. Sprague de Camp, in his book Lost Continents, wrote that Blavatsky's main sources were "H. H. Wilson's translation of the ancient Indian Vishnu Purana; Alexander Winchell's World Life; or, Comparative Geology; Donnelly's Atlantis; and other contemporary scientific, pseudo-scientific, and occult works, plagiarized without credit and used in a blundering manner that showed but skin-deep acquaintance with the subjects under discussion.

[18] Historian Michael Marrus has written that Blavatsky's racial ideas "could be easily misused" and that her book had helped to foster antisemitism in Germany during World War II.