Why we prefer people just like us. And why that may be dangerous.

In general, birds of a feather do tend to flock together.

Videos
  • It's common for people to form groups of like minded individuals who also have similar abilities.
  • Evolution confers advantages on heterogeneous groups of people and groups with diverse talent sets.
  • Prizing individual identity ahead of group identity also helps counteract tribalistic politics.


The average lifespan of a friendship? 10 years. Here’s why.

This is the psychology of why friendships (and marriages) fail.

Videos
  • Some friendships last a lifetime, but most have a lifespan. In the U.S., best friends tend to last for 10 years on average, says Nicholas Christakis.
  • In friendships, one person may begin to defect or "free ride", which causes the other person to choose between cooperation or defection. People tend to choose the latter so they won't be taken advantage of.
  • A certain amount of social fluidity, taking a breather from a friendship, can actually make a friendship last longer.
Keep reading Show less

Social capital: If you want to succeed, start making friends

In his lecture, Nicholas Christakis explains why individual actions are inextricably linked to sociological pressures. Whether you’re absorbing altruism performed by someone you’ll never meet or deciding to jump off the Golden Gate Bridge, collective phenomena affect every aspect of your life.

Videos

If you think you're in complete control of your destiny or even your own actions, you're wrong. Every choice you make, every behavior you exhibit, and even every desire you have finds its roots in the social universe. In his lecture, Nicholas Christakis explains why individual actions are inextricably linked to sociological pressures. Whether you’re absorbing altruism performed by someone you’ll never meet or deciding to jump off the Golden Gate Bridge, collective phenomena affect every aspect of your life.

The Power of Copycatting

You copy the people to whom you are connected primarily and you come to copy them along a whole variety of traits.  

One of the things that we have found in the study of networks is that whenever people are free to choose anything they want they usually choose what their friends have chosen and people tend to copy each other.  This sort of fundamental mimicry or this mimicry that we humans evince is extremely fundamental and therefore, networks provide us a kind of mathematical, social and biological tool to understand the kind of fundamental basis for this mimicry because you copy the people to whom you are connected primarily and you come to copy them along a whole variety of traits.  

Keep reading Show less