Footfalls above "we would see the tracing on the stage floor of a tremendously elongated variation of the figures 8 turned on its side … the mathematical symbol for infinity." Beckett was also indebted to the French psychologist Pierre Janet for his conception of hysterical behaviour. In his overview of Janet's work, Robert Woodworth in his "Contemporary Schools of Psychology", a work Beckett read, pays particular attention to Janet's description of the "hysterical paralysis of one arm", which Beckett incorporated, into May's posture. There are a number of analogies between "Footfalls" and Janet's work with a patient called Irène: He lists
Prime (symbol) to subscripts – "x"′ generally means something related to or derived from "x". For example, if a point is represented by the Cartesian coordinates , then that point rotated, translated or reflected might be represented as . The prime symbol is not related to prime numbers. Usually, the meaning of "x"′ is defined when it is first used, but sometimes its meaning is assumed to be understood: The prime is said to "decorate" the letter to which it applies. The same convention is adopted in functional programming, particularly in Haskell. In geometry, geography and astronomy, prime and double prime are