Psychohistory (fictional) - The Prime Radiant

The Prime Radiant

Asimov presents the Prime Radiant, a device designed by Hari Seldon and built by Yugo Amaryl, as storing the psychohistorical equations showing the future development of humanity.

The Prime Radiant projects the equations onto walls in some unexplained manner, but it does not cast shadows, thus allowing workers easy interaction. Control operates through the power of the mind, allowing the user to zoom in to details of the equations, and to change them. One can make annotations, but by convention all amendments remain anonymous.

A student destined for speakerhood has to present an amendment to the plan. Five different boards then check the mathematics rigorously. Students have to defend their proposals against concerted and merciless attacks. After two years the change gets reviewed again. If after the second examination it still passes muster the contribution becomes part of the Seldon Plan.

The Radiant, as well as being interactive, employs a type of colour-coding to equations within itself for ready comprehension by Psychohistorians.

• Seldon Black are the original Seldon Plan equations developed by Seldon and Amaryl during the first four decades of Seldon's work at the University of Streeling, and define Seldon Crises, the Plan's duration, and the eventuation of the Second Galactic Empire.

• Speaker Red are additions to the plan by Speakers (Senior Mentalic Psychohistorians of the Second Foundation) since the time of Seldon.

• Deviation Blue are observed deviations away from Psychohistorical projections with a deviation in excess of 1.5 standard deviation of predicted outcomes (1.5 σ). The Era of Deviations, at the rise of the Mule, produced deviations in the Seldon Plan in excess of .5 through 10 sigmas, and the resolution of this period required a full century of labour on the part of the Second Foundation to return the Galaxy to the Plan.

Other colours have been imagined by fans, and mentioned by Asimov, such as:

• Notation Green - additions of pertinent scientific papers appended to findings (Forward the Foundation)

• Projection Purple - Useful for determining limits on future Speaker Red equations, using projections of events with regard to a very sketchy but still monumental Seldon Black scheme. A tool of the first three generations of Psychohistorians after Seldon, and by the 5th Century of the Plan a teaching tool at most. (Forward the Foundation)