Always Wondered - Why Do We "Knock on Wood"?

On this episode, it's the history of cutlery.   How did we go from eating with our hands to needing five different forks for one meal?  We'll hand out the silverware and serve up the answer.  Also - get ready for the great debate of our time! Toilet paper:  should it hang over or under?  We'll unroll all the controversy.  Plus - why do we knock on wood to ward off bad luck?  Where did this strange ritual start?  And will Formica do in a pinch?  Join host Rick Peterson as he answers more of the questions you've Always Wondered about.