Recent Issues. Chapter 12: The Behavior of Organisms at Fifty. Quote 15 Post author:B. F. Skinner Foundation Post published:April 19, 2019 Post category:Skinner's Quote of the Day “When a response was reinforced only in the presence of the light as an S Dee, the rat responded slowly in its absence (which, unfortunately, I called S Delta, hard to print) but responded immediately when the light came on.” (p. 127) You Might Also Like Verbal Behavior: Extended Edition. Chapter 12: The Autoclitic. Quote 30 September 10, 2025 Contingencies of Reinforcement. Chapter 9: The inside story. Quote 21 October 3, 2018 Contingencies of Reinforcement. Chapter 8: Behaviorism at fifty. Quote 23 September 4, 2018