Zombies are reanimated corpses. A corpse is a dead human being, if it comes back to life, it is a zombie. Quite simple. Of course, what makes it exciting is that zombies have a terrible desire to eat living human beings, specially brains. The possible interpretation is that of want, they want what they lack, since they are dead living corpses, their brains aren’t working and they want some. However, it might simply be a craving for life and live flesh is what gives them their reanimation.
You see, if they wanted brains because of the lack, then we would not have stupid zombies. And we do have them.
For example, about 2,000 years ago this dim-witted jewish zombie got it wrong. Though he went around scaring people (you know, by doing the zombie stuff: displaying his open wounds, moving with a sluggish, blundering pace, etc.) instead of doing the proper munching up of the populace, he asked for the opposite and started telling everyone to eat him!
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