Sure it is. If I am hungry, it is an objective fact that I desire food. That may change in the future; but as long as I am hungry, it is an Objective Fact that I desire food.
First, OWK may change his mind.
Okay... and?
What you are telling me is, "2+3 only equals 5 as long as you retain the 3 in the equation!! Otherwise, 2+ (nothing) does not equal 5!!" Well, yes, that's true; but as long as you do have both a 2 and a 3 in that additive equation, it absolutely equals 5.
In like manner, if it is true (as it is) that OWK does desire to continue living, then any Social Compact which he contracts with those of like desire, must necessarily be absolute (admitting of neither alteration nor exception).
To say otherwise doesn't make any sense -- is it rational to form Social Compacts on the basis of things with no Moral Value?
Is it rational to eat when one is hungry?
The rationality in OWK's social compact is simply this: it satisfies his desire for protection against being Murdered, as eating satisfies hunger.
For that reason, your description of the genesis of OWK's "Social Compact" is artificial and completely unconvincing. It's certainly not absolute, as you claim it to be. What you've described is not an objective system at all, but merely a convenient arrangement -- one among many possible. For example, various empires have thrived for thousands of years on the basis of a social compact called Might Makes Right, and many individuals within those cultures died rich and happy after a life of conquest and enslavement.
True; but "Might makes Right" offers OWK no absolute institutional guarantee of Not Being Murdered or subjugated. If everyone in the Social Compact "Might makes Right" does what the Compact demands, then in fact OWK has a very high likelihood of being murdered or subjugated.
By contrast, in the "Non-Aggression Social Compact", if everyone in the Social Compact does what the Compact demands, then OWK enjoys an absolute institutional guarantee of Not Being Murdered or subjugated by those within the Compact (if nobody in the Compact is murdering or subjugating anybody else, then it is an absolute certainty that OWK is himself Not Being Murdered or subjugated by those within the Compact).
That's why it's called enlightened self-interest.
And so it's not an objective fact at all, merely a matter of personal preference. It may be an "objective" fact today, but the fact that his desire may be completely different tomorrow shows that this "objective" fact is really only subjective, and most likely contingent on some other set of circumstances. This is not much of a basis for an allegedly "absolute" Social Compact.
Consider: Suppose OWK decides that, instead of continuing his existence, he'd rather drive an airplane into the skyscraper in which Messrs. A, B, and C work. The conditions of the original "absolute" Social Compact are predicated on the assumption that OWK will always want to stay alive, and from that you've derived what you consider to be an absolute compact. But now OWK's desire has changed, and OWK has initiated a new Compact of his own devising. The original Social Compact is thus contingent on OWK's desire to live, and on his willingness to abide by the agreement. Clearly that compact was never absolute, but instead dependent on the subjective desires of those involved.
What you are telling me is, "2+3 only equals 5 as long as you retain the 3 in the equation!! Otherwise, 2+ (nothing) does not equal 5!!" Well, yes, that's true; but as long as you do have both a 2 and a 3 in that additive equation, it absolutely equals 5.
But wait: you've elevated OWK's "objective" desire to stay alive to the level of the "3" in this equation. You're assuming that "OWK's desire to remain alive" is of the same order as the value of "3" -- which it quite obviously is not.
Is it rational to eat when one is hungry?
Not always. For example, it may be considered irrational to eat food you know to be poisoned, or to eat when you're fasting prior to surgery. Obviously in this case there are higher "moral imperatives" which may trump the desire to satisfy hunger. It's easy to see that the same goes for a desire to remain alive.
The rationality in OWK's social compact is simply this: it satisfies his desire for protection against being Murdered, as eating satisfies hunger.
Killing A, B, and C would serve the same purpose, and in the long run it might well be a far more reliable guarantee against being murdered by them!
True; but "Might makes Right" offers OWK no absolute institutional guarantee of Not Being Murdered or subjugated.
Neither does your Social Compact: it merely trusts that a) all parties value staying alive above all things, and b) that they'll all abide by the agreement even if they change their minds.
However, once a party to the contract changes his mind, then what? If he acts on his new belief, has he done wrong? Or, because his "objective desire" has changed, is he merely acting rationally according to his current state of mind?
HumanaeVitae already discussed "stipulations and assertions" at length, and here is a prime example. You end up having to assert that the agreement, once entered into, not only won't, but can't be broken -- even though it rests only on a subjective and changeable desire to stay alive. Indeed, you have to make many, many assumptions and stipulations about the binding nature of agreements in order for the compact to remain binding on its participants.
That's why it's called enlightened self-interest.
Even if we grant that our desire to stay alive is truly an objective basis, "Enlightened Self-Interest" is a notoriously poor guide for telling us how to achieve it. For example, suppose I decide that I can get away with murdering OWK; that by doing so I will gain financial security for life; and that my newfound wealth will allow me to buy physical security as well. Why shouldn't I kill him?
Appeals to a Godless nature offer no help here -- nature operates according to Might Makes Right, wherein things like murder, enslavement, and rape are fine if they work. The only way you're going to call those things absolutely wrong, is by accepting what the good Rabbi says: that it's wrong because God said so.