In a review of biographies of Charles Dickens I found this:
In 1849 he showed a short account of his early years to his close friend John Forster, revealing a story he never told his own family: the shame-inducing months he spent, while his father was in a debtor’s prison, as a 12-year-old “laboring hind” in a factory that bottled shoe-blacking.
Suddenly I understood why he wrote Oliver Twist and why it is so good. Budding writers are told write what you know. They should be told write what you feel bad about.
The work of James Pennebaker has shown the benefits of even small amounts of self-disclosure. No doubt this is why all sorts of psychotherapy, supposedly based on enormously different theories, help roughly the same amount: All involve self-disclosure. I see this effect as something built into us by evolution to increase self-disclosure. Talking about bad experiences helps your listeners avoid what happened to you. To motivate such disclosures, evolution has built into us something that causes us to feel better after we talk this way.
Scientists are not told study what you know and they are especially not told study what you feel bad about. Scientists are mostly men, of course, and that sort of thing makes men uncomfortable. My personal science, however, suggests the correctness of this idea.