The Haertel Scholium
This term describes the background of a number of Blish's short-story science fiction. Three distinct technologies, their invention, and consequences are outlined. There is a modicum of overlap between The Cities in Flight saga and that of The Seedling Stars, mainly through one piece of technology : The Dirac Radio. Another unifying concept is the first trans-luminal drive — The Haertel Overdrive.
Adolph (Dolph) Haertel developed the drive in order to reach Mars rapidly (Welcome to Mars!). Haertel Cosmology, the result of Haertel's science, in Blish's words, "swallowed Einstein the way Einstein swallowed Newton — that is to say, alive." Haertel goes on to develop the drive to allow the entry of men into interstellar space. The DFC-3, piloted by Garrard, reaches Alpha Centauri, where extraterrestrial first contact is made with the Clinesterton Beademung (Short Story: "Common Time"). The Drive at this stage is not well developed, and initially suffers from dramatic chrono-swings from almost complete time-freeze to the hyper-time of pseudo-death. With refinement, the drive becomes a valid method of interstellar travel, though not without mishap and adventure as other forms of travel are tried, such as the near-useless (though fascinating and instructive for the quantum physicist) Arpe Drive ("Nor Iron Bars").
Refinement of the drive allows the exploration of the near-stars, as well as the Coal-Sack Nebula, wherein the beings known as Angels are first encountered by the hero Jack Loftus, Sylvia McCrary and Dr. Challenger, as well as a long lived and powerful civilization, the Hegemony of Malis (The Star Dwellers). Ultimately deduction, and a first hand experience of a planet deliberately maintained in a state of genocidal savagery ("A Dusk of Idols"), coupled with expert reasoning reveals that the Hegemony is malignant, and Humanity rebels. Journey to the Heart Stars reveals the true nature of the Hegemony, and with the help of a stowaway Angel, Hesperus, humanity is freed of its bondage, and made companions of the Angels.
The stories considered part of the Haertel Scholium include A Case of Conscience, and the Pantropy series (see below). Both are anomalous in that they do not appear to have the Dirac Radio, though it is plausible to assume that A Case of Conscience takes place before the development of the Dirac.
A unifying force of galactic civilization is the Dirac Radio, developed by Dr. Thor Wald. This radio is able to permit faster-than-light radio transmission. It has an additional and unsettling ability — within every transmission, is the sum total of all transmissions from the device, throughout all of time and space. The Department of Intelligence, headed by Captain Robert Weinbaum, and aided by the beautiful video reporter Dana Lje, make this shattering discovery. Three hundred years later, the "Service" is the dominant government of the Galaxy, and Dirac is the center of their power, with a network built from Haertel Overdrive spacelanes. ("Beep").
4000 years in the future, Human civilization has met its first full antagonist — the Green Exarchy. A system of many civilizations ruled by a non-human emperor, the Green Exarch, this represents a significant threat to High Earth. The Green Exarch has at his employ the extremely dangerous shapeshifting (protean) agents known as Vombis, who will appear human, but do not revert to their true shape when killed, giving them an air of great mystery and menace.
The Haertel Overdrive is now called the Imaginary Drive, and the Dirac is still in common use. High Earth remains the center of Human civilization. That civilization is remarkably advanced — for all practical intents, humans are now immortal. A memory cleanse known as Baptism permits those filled with ennui to begin lives anew, though there are side effects from subconscious recall. A quasi-religious group known as Sagittarians also play a part. The most important financial force in the empire of High Earth is the Traitor's Guild, who permit money to flow from system to system in reward of treachery to system governments, producing a Feudatory system between worlds, though not at the expense of internal stability. Traitors skillfully employ advanced biotechnology to further their aims, and are known to employ fungal cytotoxins, DNA reverse transcription mutation agents (to inject false memories and appearances in order to forestall recognition and testimony during interrogations), as well as technology to petrify dead bodies in order to make up wall fortifications in far offworld planets. The Traitors Guild may be found on all planets (A Traitor of Quality, Section in The Quincunx of Time with a lecture about the Traitor's Guild, and The Green Exarchy).
5000 years later still, Human civilization has gone through many Rebirths, or Renaissances. The chance infusion of a mentality from 1949 through a freak combination of the active mode of the Dirac within a Radio Telescope results in the formation, after many adventures and an ultimate resurgence of Man, the Quint, the Autarch of Rebirth V. A computer of this far future time uses the Dirac as both a means of communication and infinite memory storage (Midsummer Century). Its existence was foretold at the time of Capt. Weinbaum, though no-one could interpret its messages then (The Quincunx of Time, novella expansion of "Beep").
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