Counting Cats in Zanzibar Rotating Header Image


This is for Julie,

Dr. Schambaugh, of the University of Oklahoma School of Chemical Engineering, Final Exam question for May of 1997. Dr. Schambaugh is known for asking questions such as, “why do airplanes fly?” on his final exams. His one and only final exam question in May 1997 for his Momentum, Heat and Mass Transfer II class was: “Is hell exothermic or endothermic? Support your answer with proof.”

Most of the students wrote proofs of their beliefs using Boyle’s Law or some variant. One student, however, wrote the following:

(I would argue with the first postulate. Anything that exists must have some form of mass-energy but… Well, we can discuss further on that but that would involve quantum mechanics (best said in a codulent Germanic accent – “Kvantum Mee-chanics”) and relativity. Thermodynamics itself is a long and troubled road and involves Josiah Willard Gibbs’s Grand Canonical Ensemble (available for birthdays, weddings, bar mitvahs etc…).)

That’s a lot more complicated in practice than it looks…

…Here goes with the answer…

“First, 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? I think 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, let’s 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, then 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 all people and 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 in 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. Two options exist:

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 until all hell breaks loose.

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.

So which is it? If we accept the quote given to me by Theresa Manyan during Freshman year, “that it will be a cold night in hell before I sleep with you” and take into account the fact that I still have NOT succeeded in having sexual relations with her, then Option 2 cannot be true…Thus, hell is exothermic.”

The student, Tim Graham, got the only A.

Brilliant stuff! Brilliant from the Prof too because that is a perfect example of what the great mathematician G.H. Hardy meant by questions with a bit of “spin”. He meant that in terms of cricket and not QMech. Best not go there. I once tried to explain relativity to Paul Marks of this parish and he got upset. He suggested that when his time comes to meet St Peter he would ask God why he’d created a Universe that doesn’t make sense. Well, it’s a Universe and it’s the best one we have in that line. I do not risk the double-slit experiment with Paul.

As to why aeroplanes fly… Well, that’s quite complicated. And it is not exactly the “lies for children” what you were taught at school.


  1. Uncle Nick says:

    Entertaining it may be, I fear that it may well be one of those lovely urban legends stemming from “wouldn’t it be lovely if someone *had* said this?”.

    A quick search on the term “Is hell exothermic or endothermic” shows attribution of (a version of) this tale to:

    a University of Arizona chemistry mid term
    a University of Washington engineering mid term
    a University of Washington chemistry mid-term
    a McGill University chemistry mid-term

    And the lady in question to be:

    Theresa Manyan
    Theresa Banyan
    Therese Banyan
    Celine LeBlanc

    And that’s before we visit that pit of fun-death that is Snopes… (

  2. Julie near Chicago says:

    Well I don’t care if it’s true or not. It’s true.

    And I’d have given the guy an “A” too. For ingenuity and the ability to write good parody/satire, like the better of the old-school SF writers. (Off-hand, Fredric Brown comes to mind, but I don’t think he’s the best of them.) Logic holes big enough to drive several Airbi through, wingtip-to-wingtip, mind, but never let logic get in the way of a good story.

    *”Airbi”–plural of the obviously Latinate “Airbus.” Included as an in-joke for the bloke who didn’t realize that even comedians know the correct plural of “hippopotamus.” :>)!

    Oh–what makes an airplane fly. Well actually it doesn’t, you know. Didn’t you see “The Rescuers Down Under”? Ask Cats, he’d know all about it. Airplanes APPEAR to fly because Big Bird or one of his brood strap the plane to themselves just behind the bulbous excrescence at the front that is actually an upside-down bathtub, providing both the motive power and the steering. The only time anyone is damaged is when some lowlife like the Creature at 1600 Pennsylvania Avenue disses Big Bird. This sometimes annoys him sufficiently that he forgets about being attached to the bathtub and does a few barrel rolls and loops to shake off his bad mood. Unfortunately once in awhile the strap comes undone under the strain and, well….

    As for what holds the plane up, it takes the combined force of will and force of muscle of the entire knowledgeable passenger (and crew) contingent, together with utter dedication to their task not to budge from their seats nor let go of the armrests till the thing lands. What, you think *anti-gravity* holds it up??!!!

    In all seriousness, I really did enjoy this–thanks, Nick! And I do think whoever was the actual creator of the story did a fabulous job of making sport of our English (or American?) idioms. :>))!!

Leave a Reply

%d bloggers like this: