Dumb Drunk

A guy walks into a bar and orders a whiskey. Just before he takes a sip of his whiskey, a guy runs in and says, “Bill, your house burnt down!” So he runs outside, but then he thinks, “I don’t have a house,” so he goes back into the bar and takes a sip of his whiskey.
Another guy runs in and says, “Bill! Your dad died!”
He runs out of the bar, gets on his horse and rides a little ways, but then thinks, “I don’t have a dad,” so he goes back into the bar and drinks almost all of his whiskey. Then another guy runs in and says, “Bill! You won the lottery!”
So he runs out, gets on his horse and rides all the way to the bank, but then he thinks, “My name’s not Bill.”