Are you happy?

Today, a friend at work looked straight at me and asked, 

"Are you happy?"

Out of nowhere.

As I was handing him a ruler he had asked to borrow.

It was odd, but it wouldn't have been as odd, except he wasn't the first person to say something like that to me recently. 

He was the third.

After I laughed and told him that fact, he persisted, 

"Well, are you?"

And I said, "I don't know."

With his directness, it had hit me as a strange question. 

Am I happy? I don't know. Should I be? Is that what people ask themselves? Is that the mark of a good life? Am I unhappy because I don't worry about whether I'm happy or not? 

There must be a reason that it's important to him that I am happy--someone he shares pleasant smiles with at work but don't know all that well. There must be a reason that three people asked me that within two weeks. There must be a reason that this idea won't go away.

If I'm unhappy, is that such a terrible thing?

I don't know what to say.