There is an urban legend saying that a philosophy professor at an Ivy League college gave his students a one word final exam.
The word:
And a student wrote: "Because", then set off. 
The student got an "A".
If I was the student, I would write :"Why not?"  Provided that the answer needed not to have only one word also. 
Why love?  –why not?
Why hate?  –why not?
Why hurt?  –why not?
You can substitute any word after the "why", and the correct answer would always be "why not?"
Don’t ask me why.
Why not?