On the relationship side, if you teach people to respond actively and constructively when someone they care about has a victory, it increases love and friendship and decreases the probability of depression.

Positive thinking is the notion that if you think good thoughts, things will work out well. Optimism is the feeling of thinking things will be well and be hopeful.

Once a depressed person becomes active and hopeful, self-esteem always improves. Bolstering self-esteem without changing hopelessness, without changing passivity, accomplishes nothing.

The Fundamentalist Religions simply seem to offer more hope for a brighter future than do the more liberal, humanistic ones.

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.

Some find that very optimistic people have benign illusions about themselves. These people may think they have more control, or more skill, than they actually do. Others have found that optimistic people have a good handle on reality. The jury is still out.

Doing a kindness produces the single most reliable momentary increase in well-being of any exercise we have tested.