wtallis's reply is better than mine, but you asked me a question, so I owe you a response: > Why are you so sure? For several reasons. The best one is as foll

wtallis's reply is better than mine, but you asked me a question, so I owe you a response: > Why are you so sure? For several reasons. The best one is as follows: Any video about science for a non-technical audience featuring a well-respected scientist and lecturer is incomplete without a section that explains that "Why" questions are often the most difficult to answer because of the inherent complexity of even the simplest seeming things.