People's mood is really determined primarily by their genetic make-up and personality, and in the second place by their immediate context, and only in the third and fourth place by worries and concerns and other things like that.

Groups tend to be more extreme than individuals.

We are often confident even when we are wrong, and an objective observer is more likely to detect our errors than we are.

Ten minutes of a smartphone in front of your nose is about the equivalent of an hour long walk in bright daylight. Imagine going for an hour long walk in bright daylight and then thinking, "Now I'll get some sleep." It ain't going to happen.

Optimistic people play a disproportionate role in shaping our lives. Their decisions make a difference; they are inventors, entrepreneurs, political and military leaders - not average people. They got to where they are by seeking challenges and taking risks.

We are very influenced by completely automatic things that we have no control over, and we don't know we're doing it.

The confidence that individuals have in their beliefs depends mostly on the quality of the story they can tell about what they see, even if they see little.