To the scientists of the Renaissance, your critic was really your ally, helping you advance upon reality. Critics in science are not like drama critics, determining flops and successes. Criticism to scientists is just another means of finding out whether they're wrong, like running another experiment to see if it confirms or refutes a theory. Along with the advocacy principle of the courtroom, It is one of the best ways human beings have evolved to get closer to the truth.

Habits of thinking need not be forever. One of the most significant findings in psychology in the last twenty years is that individuals choose the way they think.

Success requires persistence, the ability to not give up in the face of failure. I believe that optimistic explanatory style is the key to persistence.

Curing the negatives does not produce the positives.

The defining characteristic of pessimists is that they tend to believe that bad events will last a long time, will undermine everything they do, and are their own fault. The optimists, who are confronted with the same hard knocks of this world, think about misfortune in the opposite way. They tend to believe that defeat is just a temporary setback or a challenge, that its causes are just confined to this one case.

The pleasant life: a life that successfully pursues the positive emotions about the present, past, and future.

Optimism is invaluable for the meaningful life. With a firm belief in a positive future, you can throw yourself into the service of that which is larger than you are.