Praxis

Praxis was a chemical compound that created spontaneous and temporary mutations of the Spiral Politic. Though genuine documented cases were rare, a powerful urban myth grew up around them. Many misunderstood praxis as a drug that created subjective hallucinations, and it was often called "the Holy Grail of hallucinogenics", but it was actually a compound of several elements that defied subatomic analysis and were unknown in the Spiral Politic's periodic table. (PROSE: The Book of the War)

The Doctor was susceptible to gases in the praxis range. (TV: The Caves of Androzani, AUDIO: Planet X) The Eighth Doctor had a reaction to the gas during the Last Great Time War. (AUDIO: A Heart on Both Sides)

The only known producer of the drug was the Pilots' Coterie, whose members used it to distort the continuum in their calculations of space-time events for piloting ships like the Bababadalgharaghtakamminarronnkonnbronntonnerronntuonnthunntrovarrhounawnskawntoohoohoordenenthurnuk. Their praxis took the form of a tasteless gelatinous biomass, and humanoids needed to ingest at least 10 times their own body weight before it had any useful effect. However, there were many more efficient sources beyond the frontier in time.

Praxis played a role in Earth's history, as well. The Sargossa manuscript, recovered in the early nineteenth century by Count Potocki, recounted von Worden's experience of becoming trapped in a series of nested and regressive states of existence. The Rivera Manuscript described a similar praxis fugue, this time forced on a renegade of the Great Houses by the enemy. It apparently depicted a version of the enemy's first invasion of the Homeworld. A note on the manuscript, written in English but by an alien hand, said, "Praxis is not a drug. Praxis is not a weapon. Praxis is not a training manual. Praxis is what we were meant to become." (PROSE: The Book of the War) Avus fell into a pool of praxis in an alter-time realm and also experienced a fugue. (PROSE: Cobweb and Ivory)

House Xianthellipse sponsored the ruling caste of a posthuman colony to produce the drug for them; Robert Scarratt became addicted to praxis during his time working there. Under its influence, he (reportedly) single-handedly defused a local uprising caused by native resentment at the rulers' high-handed attitudes. In reality, his native contacts undoubtedly played a major role. (PROSE: The Book of the War)

Octavia Sutherland once sent a group of Cousins into a disintegrating praxis-liner to rescue "some trinket". (PROSE: Warring States)

Godmother Antigone of Faction Paradox sent Cousin Rupert to Bankside to investigate Haribeaux's Blue Praxis experiments; however, these claims were merely an excuse to ensnare Rupert into Father Christèmas' plan. (PROSE: Weapons Grade Snake Oil)