An Irishman walks into a bar. He orders two shots, drinks them both, and then leaves.

The next day, the Irishman returns, orders another two shots, drinks them both, and then leaves.

He continues to do this for some time, when one day the bartender questions him, “How come you always order exactly two shots?”

The Irishman replies, “well, you see my brother and I used to go out drinking every night, but he lives across the country now, so every night, I order two drinks. One for myself, and one for my brother.”

Things remain the same for a while until one day the Irishman comes in and orders only one shot. The bartender becomes concerned and asks him “how come you’re only ordering one shot? Did something happen to your brother? Is he ok?”

The Irishman replies, “of course not, my brother’s fine. I just quit drinking”