Why? The theory he came up with
just got mentioned in Scientific American.
The Big Bang Theory Season 8, Episode 18
Why are we fighting?
The Big Bang Theory Season 7, Episode 10
Why would you do that?
The Big Bang Theory Season 5, Episode 17
If one Hand can die,
WHY not a second?
Game of Thrones Season 1, Episode 5
That's WHY you had him executed.
Game of Thrones Season 2, Episode 1