Wal-Mart's size and scale is so vast they literally have the ability to change the face of the entire country. If Wal-Mart were to make a decision tomorrow to refuse to sell a single product made with partially hydrogenated oils, for example, we'd probably see rates from heart disease decline a few years later. That's how powerful Wal-Mart is.

A poor leader will tell you how many people work for them. A great leader will tell you how many people they work for.

We pursue exercise even though empirically we see no benefit from the energy we're spending and we're hurting. So empirically we should quit. The why is exactly the same thing. You persist even though there are some short-term stresses and even though there is some uncertainty.

How can you help the human race progress?

A five minute call replaces the time it takes to read and reply to the original email and read and reply to their reply... or replies. And I no longer spend 20+ minutes crafting the perfect email - no need to.

The irony is that the best thing we can do is, well one option, is to quit job we don't like. You don't always have to quit, and quite frankly, option two is to try to help others solve the problem that you are struggling with.

The goal of life is not to have our lives mean something to ourselves. The goal of life is to have our lives mean something to others.