From Saturday Live, Radio 4, 28-12-13:
Doubt is not the opposite of faith. Doubt is healthy and many problems in the world are caused by certainty. Can be painful to live with, part of human condition. Useful to have a certain amount of humility, doubt and uncertainty - it is healthier condition than rigid certainty and the feeling that you are right. Perhaps we all need to accept doubt and be open to new arguments and ideas.