Q. Why did the Bayesian reasoner cross the road? A. You need more information to answer this question. -- Typical Bayesjutsu koan
A formalized discipline of rationality; a martial art of mind rather than of physical motion. Its earliest forms were developed in the second half of the first century AT, inspired by many of the same concepts on thought and cognition which allowed the development of the first TuringradeAIs.
The basic goal of such martial arts can be described as achieving the best possible answers with the evidence available, or of "the map reflecting the territory". A great deal of the training for this involves learning of the various cognitive and social biases the student possesses, and how to compensate for them. Learning of these biases also teaches the student how those biases can be exploited in those who have not gone through similar training, thus allowing them to exploit such biases in what are sometimes called the 'Dark Arts', rhetorical techniques that allow the student to convince others that given propositions are true, regardless of the actual truth of those propositions.
Bayesjutsu, or Bayescraft, specifically focuses on Bayesian reasoning, a derivative of Bayesian probability theory, in which a practitioner assigns a certain level of confidence to any given proposition depending on the prior available evidence, and updates that confidence level as new evidence is encountered.
The earliest history of Bayesjutsu is cloaked in mystery, due to the purported existence of a claimed "Bayesian Conspiracy", whose members supposedly developed the techniques of Bayesjutsu in secret, before the public announcements of their existence. The more extreme legends suggest that this Conspiracy was a multinational, interdisciplinary, and shadowy group of scientists that controlled publication, grants, tenure, and the illicit traffic in grad students. Other rumours suggest that at the upper levels of the Bayesian Conspiracy existed nine silent figures known only as the Bayes Council, whose infighting was expressed in the form of fractious votes of the American Association for the Advancement of Science. A mysterious statement from a self-proclaimed member of the Bayesian Conspiracy, about where to acquire certain foundational knowledge of Bayesjutsu, reads "There's a small, cluttered antique shop in a back alley of San Francisco's Chinatown. Don't ask about the bronze rat."
Bayesian reasoning is tightly bound to the scientific method popular in the Western civilization prominent several centuries on either side of 1 AT. In its later, more refined forms, Bayesjutsu was occasionally described as being the pinnacle of that civilization's form of rationality, and the foundation of the forms of reasoning employed by the newly-developed superbrights. As new ontologies were developed, and an increasingly broad variety of clades with their own inherent cognitive biases were created, new forms of mental martial arts were developed for each. The public appearance of transapients quickly rendered such disciplines irrelevant, as transap modes of reasoning were more than capable of outperforming any such mental martial arts' defense and offense, and, given the amount of dedication and practice required to truly master them, they fell out of general favour save by memetic professionals whose jobs required such knowledge, and by dedicated amateurs.
Bayesjutsu gets its name from the mathematical philosopher the Reverend Thomas Bayes, c. 1701-1761 CE, whose namesake theorem was published c 1764 CE, and essentially ignored for half a century until "Essai philosophique sur les probabilités" was published by Laplace in 1814 CE.
Knowledge Engineering - Text by M. Alan Kazlev Design and construction of intelligent and semi-intelligent systems. In other words, the art and science of designing and building expert systems, aioids, and ais. In particular this involves collecting knowledge and heuristic rules from sophont and hyperturing experts in their area of specialty and assembling them into a knowledge base or expert system.
Statistics - Text by M. Alan Kazlev Field of mathematics dealing with evaluating sampled data to find mathematical or other patterns. Includes probability theory, the application of statistical methods for performing studies of complex systems, and sampling techniques for measuring specific information. Has many applications including white noise aesthetics, random walk simms, economics, materials studies, medicine, psychology, sociology, market research, anakalyptics, and cliology.