Peak–end rule end. The effects of the duration of an experience upon retrospective evaluation are extremely slight. Fredrickson and Kahneman labeled this phenomenon "duration neglect". The peak–end rule is applicable only when an experience has definite beginning and end periods. A 1993 study titled "When More Pain Is Preferred to Less: Adding a Better End" by Kahneman, Fredrickson, Charles Schreiber, and Donald Redelmeier provided groundbreaking evidence for the peak–end rule. Participants were subjected to two different versions of a single unpleasant experience. The first trial had subjects submerge a hand in 14 °C water for 60 seconds. The second trial had subjects
Equal authenticity rule be printed and published in both those Languages [i.e. both English and French]." The rule requires courts to treat "both [the English and French] versions of statutes [as] equally valid and authoritative interpretations of the law," The rule holds that both versions are equally authoritative even if the statute in question was clearly drafted in one language and translated into the other, and even if the two versions of the law are incompatible. An early version of the principle may be found a statute of the Parliament of the Province of Canada, enacted in 1857. The "Act respecting the Codification