Because good deeds spread out and cover so much more than bad deeds, because every time someone sees a good deed, they are encouraged to do another, and then they all connect and create other good deeds, and so on and so forth. It's something about when someone does something good, whether it be helping someone out, or standing up for what's right, it kind of reminds us of the good in people. Those are the sort of things that we can truly connect with, for they show us the hope that is in the hearts of those that care enough to give a shit about other human beings.
Kind of like when someone does that good samaritan thing or when a neighborhood gets together for a family in need, word of that kind of stuff travels very fast. Everyone enjoys hearing about them because they encourage us and help us believe that the world can be a better place. It kinda almost makes a ripple affect for others to do it do something nice and helpful, a chain reaction of good stuff.
This is the type of good will is contagious, in that it seems to parallel our wishes for a better world. They provide us with something to believe in, something to follow, something to be a part of that is greater than ourselves. That means, if we can see other people do good, then that means that we, too, can change. This is why good actions have a greater social reach—they touch our hearts and motivate us to share them with others, spreading the message of kindness and hope far and wide.
In a world where everything appears to be ripping us apart, the random acts of kindness show that in some way we are still connected and if we help one another enough, then maybe we can make a difference.
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