Say What Now?

Let's find out the origins of "Rule of Thumb", "No pain, No Gain", "Murphy's Law".  Thank you so much for listening!

We say them all the time, but do we even know what they mean?  "Knock on Wood" - Why? Who said it first?  What does it actually mean or refer to?  Why is third time a charm and not the second time, or ninth time?  Who is Murphy and what exactly is his law?  Let's discover saying origins!