Chapter 9 is on the chances of you meeting someone on a plane for example and having a common friend. similar to the six degrees of separation. Which is not unlikely with the rate people are connecting on social media its very likely to meet someone new that knows your friend. You can even get an example of this when you go on Facebook and it shows you mutual friends between you and your other friends.
The Epilogue Shirky sums things up talks about how fast our society is growing. how technology is constantly growing and advancing and changing our society. He points out how when calculator were first being used in school some did not accept it. Then when the birth control pill came out and how it changed things for society. What sentence that sticks out to me is when Shirky says “They changed society precisely because no one was in control of how technology was used, or by whom”. That stuck out to me because it makes you wonder how far are we going to go with technology.