Incompetence is certainty in the absence of expertise. Overconfidence is certainty in the presence of expertise.

Change your mind about something significant every day.

We tend to credit those who create an idea, not those who perfect it, forgetting that it is often only in the perfection of an idea that true progress occurs. Putting sixty-four transistors on a chip allowed people to dream of the future. Putting four million transistors on a chip actually gave them the future.

I think that persistence and stubbornness and hard work are probably, at the end of the day, more important than the willingness to take a risk.

You can learn as much - or more - from one glance at a private space as you can from hours of exposure to a public face.

If we think about emotion this way - as outside-in, not inside out - it is possible to understand how some people can have an enormous amount of influence over others. Some of us, after all, are very good at expressiing emotions and feelings, which means that we are far more emotionally contagious than the rest of us.

If you don't contradict yourself on a regular basis, then you're not thinking.