flux and reflux, ebb and flow". Accordingly, manifest existence is an eternally re-occurring event on a "boundless plane": the playground of numberless Universes incessantly manifesting and disappearing, each one "standing in the relation of an effect as regards its predecessor, and being a cause as regards its successor", doing so over vast but finite periods of time. 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." The individual souls are seen as units of consciousness (Monads) that are intrinsic parts of a universal oversoul, just as different sparks are parts of a fire. These Monads undergo a process of evolution where consciousness unfolds and matter develops. This evolution is not random, but informed by intelligence and with a purpose. Evolution follows distinct paths in accord with certain immutable laws, aspects of which are perceivable on the physical level. One such law is the law of periodicity and cyclicity; another is the law of karma or cause and effect. Theories on human evolution and race 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. The steps in this evolution are called rootraces, seven in all. Earlier rootraces exhibited completely different characteristics: physical bodies first appearing in the second rootrace and sexual characteristics in the third. Some have emphasized passages and footnotes that claim some peoples to be less fully human or spiritual than the "Aryans". For example, "Mankind is obviously divided into god-informed men and lower human creatures. The intellectual difference between the Aryan and other civilized nations and such savages as the South Sea Islanders, is inexplicable on any other grounds. No amount of culture, nor generations of training amid civilization, could raise such human specimens as the Bushmen, the Veddhas of Ceylon, and some African Tribes, to the same intellectual level as the Aryans, the Semites, and the Turanians so called. The 'sacred spark' is missing in them and it is they who are the only inferior races on the globe, now happily – owing to the wise adjustment of nature which ever works in that direction – fast dying out. Verily