Whilst HPB was engaged on this work, Mr A P Sinnett was receiving from the Master K H a series of more than 100 letters (including a few from the Master M) setting out the framework of a philosophy which was completely new to the profane world.  These letters included specific information about the great cycles of existence which set the stage for our present cosmic scene and include the coming into being of our earth, about Rounds and Races and much else.  They gave a detailed description of the after-death states and processes - also never before made public

The Letters contained the sevenfold classification of man's principles, later used by HPB in The Key to Theosophy.  These not only laid down and described the elements of man's inner being but established a nomenclature, an enumeration of the principles which is used throughout the vast theosophical literature.  These Letters ended in about 1885 and thereafter, apart from HPB's articles, there was no major outpouring of theosophical knowledge direct from the Masters.  Then came HPB's master-work, The Secret Doctrine, in two volumes, about 600 pages each, the volumes being entitled Cosmogenesis (Vol I) and Anthropogenesis (Vol II).  The first significantly expanded the teachings extant in the exoteric Eastern religious literature, including the 'creation' theme and the nature of the Absolute. The idea of there being two Unities was propounded: the unmanifest One (the Absolute) and the periodically manifest One (the ONE ALL), the latter forming the basis of all existence regarded by many as the total Cosmic Maya.  The Secret Doctrine goes on to explain how everything thereafter comes to be and to be as it is.  This account has regard to the ancient eastern teaching of the Akasha, but expands it with information on the nature and function of the Elementals.

All this 'Becoming' of the One Life, by way of an infinity of forms is all subject to the direction of the One Universal Divine Law, eternally operative.  This Law includes all aspects of Karma as used in other religious works but it clarifies many obscurities and exposes much that is erroneous in them.  Reincarnation is included in the workings of the Law; a proper understanding of which involves a knowledge of the sevenfold constitution of man.

In Anthropogenesis the whole evolutionary process of life on earth is unfolded with particular reference to man.  This information is much misunderstood by those students who tend to regard all that is said in The Secret Doctrine as applicable only to the physical plane.  It is this plane which is being specifically investigated by science.  The SD deals with life on the inner planes of existence which corresponds exactly to the 'principles' of man's constitution.  The cosmic process of Life ever-becoming is unimaginably long, in terms of earth time many millions of years.  Vol II is the story of the evolution of life in its various forms on various globes, as well as in the subjective realms. This process covers periods of time never dreamt of by orthodox science.  All this information was absolutely new when it was first divulged in these writings.  Towards the end of her life, HPB wrote The Key to Theosophy, forming in brief, in question and answer form, an outline of the main tenets of Theosophy, stressing its practical applications.  She followed this quickly with The Voice of the Silence, a unique inspirational book of descriptions of the path and instruction for the serious pilgrim.

The foregoing is merely to whet the appetites of the truly inquiring students, who would explore the depths of our theosophical teachings.  The advent of Theosophy in these terms was indeed a world event.  Another unique feature about this outpouring was that the Masters concerned gave it out either by themselves or through HPB under their direction.  She had periods of intense training and developed remarkable psychic and spiritual faculties and, from about the age of 40 until she died at the age of 59, she devoted her whole life to the task.  This involved her in a sacrifice of her health and entailed much suffering.

The story of her writing of these enormous works is an epic in itself.  Never before had the inner hierarchy made so much information directly available.  No other world teacher had ever written anything.  What we have of their teachings was what was remembered and written by their followers sometimes generations later.  In the case of Theosophy we have the literature actually uttered by the Masters through HPB as an amanuensis, and that in itself makes it unique.  From the start some Indian pundits opposed the writing of The Secret Doctrine (see SD  I, Introduction by de Zirkoff, pp. 45-96).  This may have had Karmic results; for example, is it not significant that The Secret Doctrine has not been translated into an Indian language and so cannot be studied there in the vernacular?  There are no doubt initiated Brahmans but they are under a vow of secrecy so the actual content of the SD in many aspects is little known in the East.