As Billy Crystal's eccentric, miracle-working hermit character told us in The Princess Bride, there's a big difference between mostly dead and all dead.
With Meredith's life hanging in the balance, Grey's Anatomy Insider's Seattle correspondent did some brief research to learn how dead our heroine actually is medically. What we learned, at least from the perspective of non-medical experts, is that the situation is grim, but hopeful. See below.
This week, Meredith came out of the water, completely blue from the hypothermia and not breathing.
Also? She might be dead.
So how often do people really come back from the dead?
Well, Meredith Grey was completely under water for quite some time.
During that time, she most likely inhaled some water into her lungs, which can lead to asphyxiation and drowning. But the water Meredith was in was very cold, which actually increases her chances of survival.
According to Wikipedia's article on drowning, extremely cold water slows down the body's metabolism, leading to decreased levels of oxygen and blood flow. This can mean that a person who is submerged in cold water for an extended period of time can sort of come back to life.
On the other hand, such cold water led Meredith to become hypothermic, meaning her core body temperature is dangerously low - somewhere around 81 degrees - just before she went into the light and saw Denny and Dylan.
How often do people survive such a harrowing ordeal?
According to Princeton University studies, human beings who are in severe hypothermia will appear dead, but may actually be in a "metabolic icebox," meaning, they can be revived.
The heart is probably still beating, albeit very slowly, but if enough blood is circulating, it could be enough to keep the person alive until they can be warmed up.
Apparently, there have been cases where people who were hypothermic have been given CPR for up to three and half hours and have still recovered without any long-term damage.
In short, there's still hope for our girl, Meredith.
If you can look past the fact that she's the color of a Smurf right now and realize that the supposed best doctors in the country are all gathered around her hospital bed, you'll find a glimmer of hope that she'll pull through.