For internal dating and time standards the polises use CST (Coalition Standard Time), measured in "tau" elapsed since the adoption of the system on January 1, 2065 (UT). The novel begins at CST date "23 387 025 000 000". CST defines one tau as the amount of time in which a polis citizen can experience the passage of one second of "subjective" time; this elastic value changes with improvements in polis hardware. In the period of the novel a polis citizen's mind can operate at a maximum speed of about eight hundred times that of a flesher's mind, so 1 tau equals approximately 1/800 s. By the beginning of the novel, the Coalition of Polises has had just over 741,597 years of recorded history, amounting to 910 years of flesher history; almost all of the Coalition's history, about 98.3% of it, has occurred (from the flesher's perspective) within the very recent past, since the last major Coalition-wide polis hardware upgrade in UT 2750.