Replace the question mark with a number

A man who smelled like a distillery flopped on a subway seat next to a priest.

The man's tie was stained, his face was plastered with red lipstick, and a half empty bottle of gin was sticking out of his torn coat pocket. He opened his newspaper and began reading.

After a few minutes the disheveled guy turned to the priest and asked, "Say, Father, what causes arthritis?"

"Mister, it's caused by loose living, being with cheap, wicked women, too much alcohol and a contempt for your fellow man."

"Well, I'll be damned!" the drunk muttered, returning to his paper.

The priest, thinking about what he had said, nudged the man and apologized. "I'm very sorry. I didn't mean to come on so strong. How long have you had arthritis?"

"I don't have it, Father. I was just reading here that the Pope does."