How will you measure your life: Lesson 3: Avoid the trap of marginal thinking.

One relationship we mustn’t neglect in all this is the one you have with yourself. A really easy way to protect it at all times is to live with integrity. If your conscience is clear, you’ll feel good about decisions you make and actions you take, and that’s what makes those work out.

For most people, integrity is the default setting. Where we wander off the path of doing what’s right is where it gets icky. How can you avoid compromising your integrity?

Simple: recognize marginal thinking and don’t engage in it. What’s marginal thinking? It’s when all you think about are the “edges” of the situation.

For example, Blockbuster was the incumbent in the movie rental market for a long time. One day, a little company called Netflix started sending out DVDs via mail and had customers return them that way. Weirdos! Because they didn’t want to pay the marginal costs of adding this service to their own portfolio of products, Blockbuster ended up paying the ultimate price instead: they went bankrupt in 2010.