Self-criticism can seriously injure potential talent that wants to be expressed. It nags and predicts doom until I get a splitting headache.
Artists are either celibate or gay.
The point Cameron is making is that such beliefs, regardless of fact, can profoundly stifle creative expression and the life choices that enable creativity. They describe in the book a powerful cognitive therapy kind of exercise that helped Joanna. Cognitive therapy can be as effective as drugs in treating depression and anxiety, and works by helping make conscious typically hidden automatic thinking, beliefs and self-talk. After getting more aware of this critical inner voice through counseling, plus journal-writing, Joanna was able to establish a successful business that engaged her creative talents. But I've experienced benefits from therapy myself, and I think of it as a potentially valuable tool for better realizing creativity.