In this Easter-octave Sunday it is appropriate to reflect on the need for "resurrection from the dead" to have a benevolent supernatural Source. I am not here proving or even basing this discussion on the reality of the resurrection of anyone from the dead, but simply using it as an illustration. In fact the basis of my argument is purely natural.
This theorem is called "No-Zombie"1 because it explains why there are no evil "undead" beings, and their existence is, if not impossible, at least highly unlikely. This principle is in some sense the flip side of the principle of Super-Natural Selection. It is important to note that I'm not positing this principle as an iron-clad, mathematically inviolate law, but as a general rule that helps us make sense of the world.
The fundamental point to consider is the existence, or rather non-existence, of evil. While we might intuitively believe that evil exists, in fact it does not. What we call evil is in fact lack of a due good or due order.
For example, a man missing a limb is the subject of a physical evil: he lacks the arm or leg proper to a human being; but the man himself is not evil. The lesson to take is that physical evil has no existence in itself, but only exists in a subsistent thing; evil is parasitic.
Similarly with regard to human actions: evil acts are not ordered to man's ultimate good (i.e., the happiness of life as a whole), though they are ordered to inferior goods. Take bank robbery for instance: taking what belongs to others is clearly wrong; it does not conform to the good of society, and ultimately to the good of the thieves themselves. But notice that the thieves don't just out-of-the-blue choose evil for its own sake: they seek a good (gaining wealth), but their means are inconsistent with the overarching good of the just2 ordering of society, not to mention the just ordering of their wills. A more mundane example: a person may, despite being on a diet for health reasons, choose to devour a whole pint of ice cream: he is not positively choosing to violate his diet, but rather ignoring his diet to choose the more immediate good of ice cream. He has set aside the greater good of his health for momentary gratification: a disordered choice not consistent with the greater happiness of his life.
There are in fact a hierarchy of goods. Extrinsic goods, like monetary wealth, are at the bottom. Instrinsic physical goods, like health, are just above them, because one cannot gain or maintain wealth without health. Above these are spiritual goods, which are more integral to the human person and thus less easily lost; examples include education, good habits (i.e., virtues). (Notice that I mean spiritual in a purely natural sense.) These spiritual goods are what enable one to gain and maintain the inferior goods; for example, education in proper hygiene is necessary to maintain health; a people's habit of settling disputes peacefully is necessary to gain and maintain a wealthy society.
Despite our modern tendency to absolutize ideas and ideals by investing them in actual flesh-and-blood people (e.g., American Presidents are popular subjects for this), no human being (in fact no being) is fully evil.3 Bill Clinton or George Bush (or your favorite whipping-boy) may for you epitomize all that is wrong with the world, but he is not the incarnation of evil (nor for that matter is he the incarnation of good). To incarnate evil would be to incarnate all disorder: and the ways to be disordered are infinite. If whosie-bob incarnated evil, he would be unable even to get out of bed in the morning; he would lack the will-power to organize meetings, or even to maintain his own health. And clearly, for a man to achieve high public office, he has to possess some virtues (and for that matter it also seems he must have done something wrong).
Though it often happens that people use whatever good they posses (wealth, strength, discipline) to commit evil acts, such acts undermine their agents and make any power they possess fleeting.4 Evil has its moment; God has His eternity.
The bottom line is that evil, since it has no existence of its own, ultimately kills its host and neutralizes itself.
That is why there are no zombies, and rising from the dead (and especially in a glorified body) can only be the fruit of the power of the Creator.
1. Not to be confused with the "No Zombie" property of computer science.
2. A short definition of justice: giving each man his due.
3. The Devil is not completely evil: recall that he was once an angel, but turned against his Creator. Even now he still possesses some good: the existence he owes to God.
4. Only naively is this equivalent to "might makes right," or rather "right makes might". One must expand one's hosizon to long-range "might" to make the latter true.