Heaven and Hell

A friend of mine studying at a certain Ivy League university posted this on Facebook today:

Sign at the divinity school: “I believe that HEAVEN and HELL are REAL! Do you?”

Scrawled comment #1: Depends on what you mean by “heaven” and “hell”.
Comment #2: How do you define “real”?
Comment #3: Or “believe”?
Comment #4: What is this “I” and “you” of which you speak?