The common good is the benefit or interests of all.
ex. "it is time our elected officials stood up for the common good"
Ivan pavlov introduced the concept of CONDITIONING when he taught a dog to salivate at the sound of tuning fork
The same condition happen to human. Our brain response to our exact habitual conditioning that's why sometimes it's very hard to lose/change a habit.
For example, if you condition yourself that you need to hold some sort of doll before you went to sleep, it will be hard for you to sleep if somehow that doll is not in your possession<span />
The correct answer is "Emory Bogardus's research on social distance". Emory Bogardus designed a Social Distance Scale for measuring attitudes toward racial and ethnic groups. Bogardus believed that the more prejudiced is a person against a race or ethnic group the less he would like to interact with someone that belongs to that group. He applied this concept to make the Social Distance Scale.
One of the main causes was the rise of the Nazi party in Germany. Other considerable causes could be issues from past wars such as WW1. The effects were from the Cold War. There was a lot to break down. Some historians did tons of work to bring you and I this knowledge that's for sure.
Hope this is the answer you were looking for and that it helps. :)
