> A retiring physics professor was setting his last exam for a graduate
> course in statistical thermodynamics. Being a bit bored with it all, yet
> still maintaining a wry sense of humor, he set a single question on the
> sheet:
> 
> "Is Hell endothermic or exothermic?  Support your answer with a proof."
> 
> He had little idea what to expect, or how to grade the results, but
> decided to reward any student who was able to come up with a reasonable
> and consistent reply to his query. The following is the one "A"
> that was awarded on the exam:
> 
> We postulate that if souls exist, then they must have some mass. If
> they do, then a mole of souls can also have a mass. So, at what rate are
> souls moving into Hell and at what rate are souls leaving?
> 
> We can safely assume that once a soul gets to Hell, it will not leave.
> Therefore, no souls are leaving.
> 
> As for souls entering hell, lets look at the different religions that
> exist in the world today. Some of these religions state that if you
> are not a member of their religion, you will go to Hell. Since there
> are more than one of these religions and people do not belong to more
> than one religion, we can project that most souls go to Hell.
> 
> With birth and death rates as they are, we can expect the number of
> souls in Hell to increase exponentially.
> 
> Now, we look at the rate of change in volume of Hell. Boyle's Law states
> that in order for the temperature and pressure in Hell to stay the same,
> the ratio of the mass of souls and volume needs to stay constant.
> 
> There are two possible conditions.
> 
> If Hell is expanding at a slower rate than the rate at which souls
> enter Hell, then the temperature and pressure in Hell will increase
> exponentially until all Hell breaks loose. We'll call this Condition
> One.
> 
> Conversely, if Hell is expanding at a rate faster than the increase
> of souls in Hell, then the temperature and pressure will drop
> until Hell freezes over. Condition Two.
> 
> We can solve this with the 1990 postulation of Theresa LeClair, the
> girl who lived across the hall from me in the first year residence.
> Since I have still not been successful in obtaining sexual relations
> with her, Condition Two above has not been met. Thus it can be
> concluded that Condition One is true. Therefore, Hell is exothermic.