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) sequences (e.g., "L" means "turn the left face 90 degrees clockwise", whereas "L′" means "turn the left face 90 degrees counter-clockwise"). The prime symbol is used in combination with lower case letters in the Helmholtz pitch notation system to distinguish notes in different octaves from middle C upwards. Thus c represents the C below middle C, c′ represents middle C, c″ represents the C in the octave above middle C, and c‴ the C in the octave two octaves above middle C. A combination of upper case letters and sub-prime symbols is used to represent notes in lower octaves. Thus