Brian convinces his friend Joe, who prefers to stay home and play video games all day, to go for a hike in the woods one sunny afternoon. During the hike, Brian jokingly pushes Joe and Joe falls over a ravine and suffers severe injuries. Feeling terrible, Brian carries Joe on his back all the way to the nearest hospital and leaves him in the emergency room. After Brian leaves, Joe enters the restroom under his own power and passes out. Joe eventually dies from internal bleeding in the emergency room bathroom. Is Brian the proximate cause of Joe’s death? Why or why not? Explain what doctrine, if any, applies.