TIL about The Bystander Effect, an apparent social phenomenon where individuals are less likely to intervene in an emergency situation if others are present, increasing on the number who are there. It was popularised after the 1964 Kitty Genovese murder.

Just want to add, I know this is a disputed trend, especially in the case of Kitty Genovese. I just found it very interesting.

The apparent lack of reaction by numerous neighbors purported to have watched the scene or to have heard Genovese's cries for help, although erroneously reported, prompted research into diffusion of responsibility and the bystander effect. Social psychologists John M. Darley and Bibb Latané started this line of research, showing that contrary to common expectations, larger numbers of bystanders decrease the likelihood that someone will step forward and help a victim.[62] The reasons include the fact that onlookers see that others are not helping either, that onlookers believe others will know better how to help, and that onlookers feel uncertain about helping while others are watching. The Genovese case thus became a classic feature of social psychology textbooks in the United States and the United Kingdom.[23]

In September 2007, the American Psychologist published an examination of the factual basis of coverage of the Genovese murder in psychology textbooks. The three authors concluded that the story was more parable than fact, largely because of inaccurate newspaper coverage at the time of the incident.[23]

According to the authors, "despite this absence of evidence, the story continues to inhabit our introductory social psychology textbooks (and thus the minds of future social psychologists)." A survey of ten leading undergraduate psychology textbooks found the Genovese case in all ten of them, with eight textbooks suggesting that witnesses watched from their windows as Genovese was murdered, and two textbooks stating that some or most of the witnesses heard but could not see the attack.

:https://en.wikipedia.org/wiki/Murder_of_Kitty_Genovese#Psychological_research

/r/todayilearned Thread Link - psychologytoday.com