Catch 22!

Hi there, sorry for the absence but it has been truly busy days, although that doesn't really work as an excuse. I have been a bit off to actually be able to write something, but I am begining to feel bad that I don't. Thus a catch 22 situation, what is a catch 22? Well it is a non-win situation, feel bad if I do and feel bad if I don't.
Since I tried not writing, today I decided to write :P. So a lot has been going on, migrating my system into Linux at work, setting everything up, which might be an interesting post. Also the conference paper, some editing in it, hopefully it will be off my desk soon (although there is already another on the forge). Working on my PhD, meaning programing software agents to communicate, after which I need to make them collaborate. Preparing a lecture that I am giving next week on Robot Actuators, so basically revisiting my electrical engineering background, and being amazed of the things I still know and disappointed at the things I don't (Catch 22 :P). Waiting to hear the green light to move into the new house, I really want to move. I mean after something is decided it just pisses me off to drag it, but maybe it is just me... And a couple of other things also I had to deal with...
So as you can see the busy is clear :P, I really wanted to write the post about my Christmas surprise, but the video is in my Portuguese mobile, so it will have to wait. Nevertheless it is on the pipeline with high priority.
Well today is dedicated to create the slides for the lecture, so I guess this is it for today...

The prototypical Catch-22, as formulated by Heller, involves the case of John Yossarian, a U.S. Army Air Forces bombardier, who wishes to be excused from combat flight duty. In order to be excused, he must submit an official medical diagnosis from his squadron's flight surgeon, demonstrating that he is unfit to fly because he is insane. In order to get the diagnosis, he must approach the surgeon to ask for one.

Here some Wiki trivia :P

However, “catch 22” — the twenty-second of the guidelines used by military surgeons to “catch” those falsely claiming to be insane — is that an insane person should not believe or suspect that they are insane. Thus, to be recognised as insane, a person must not ask for an evaluation, because doing so implicitly shows that they suspect themselves to be insane. But, if a person does not ask for an evaluation, they cannot be recognised as insane because the evaluation is the method by which such recognition would occur. Thus, nobody can ever classify themselves as insane (even if they genuinely are), and thus nobody may ever use an insanity diagnosis to escape flying combat missions, ignoring the possibility of someone else recommending an evaluation for a peer.

A logical formulation of this situation is:

1. (Premise: If a person is excused from flying (E), that must be because they are both insane (I), and request an evaluation (R));
2. (Premise: If a person is insane (I), they should not realise that they are, and would thus have no reason to request an evaluation)
3. (2, Definition of implication: since an insane person would not request an evaluation, it follows that all persons must either not be insane, or not request an evaluation)
4. (3, De Morgan: since all persons must either not be insane, or not request an evaluation, it follows that no person can be both insane and request an evaluation)
5. (4, 1, Modus Tollens: since a person may be excused from flying only if they are both insane and request an evaluation, but no person can be both insane and request an evaluation, it follows that no person can be excused from flying)

The above describes the concept commonly referred to by the phrase “Catch 22”. The book adds an element of complete absurdity to the situation, adding that the same regulations also stipulate that (because flying combat missions is so dangerous) any sane person would not willingly fly combat missions. Thus, any person who flies missions must be insane and thus should only need to be evaluated in order to be excused from flying. However, because requesting an evaluation is a sign of sanity, no pilots are grounded for insanity. The “catch 22” statement is the only reason anyone is in the air at all.