If death is defined as the impossibility of revival, then saying someone cannot be revived because they are dead is obviously a circular argument. Yet this is the most commonly used argument against cryonics. It is said that cryonics cannot work because cryonics patients are dead. While this sounds profound, it says nothing. Mathematician Thomas Donaldson put it best:

“It is not possible to argue this question of irreversibility in the terms in which it is usually asked. At present, for most injuries and diseases, the custom is to take those who are afflicted with them, put them in boxes, and bury them. When, because of this treatment, they decline still more until they become dry bones, these dry bones are then exhibited as evidence for the irreversibility of death and the folly of believing that dead people might ever be restored to life. It is one point of cryonics that WE DO NOT INTEND TO ALLOW MATTERS TO GO THAT FAR.”

— from A Brief Scientific Introduction to Cryonics
by Thomas Donaldson, PhD

Saying that cryonics patients are dead (by contemporary medical standards), and then extending this into an absolute prognosis amounts to semantic bait-and-switch. Flawed contemporary criteria are first used to attach the label “dead”, and then this label is upheld as evidence of absolute irreversibility, which is a different meaning of the word entirely.

Rather than saying cryonics cannot work because cryonics subjects are dead, it would be more honest for skeptics to say that cryonics cannot work, therefore cryonics subjects are dead. Whether cryonics patients are in fact dead is the central question of cryonics.

Whether cryonics patients are truly dead will ultimately be determined by science, not word games. Language will eventually change to accommodate future advances in resuscitation. If not, one day there could be a conversation like this:

McCoy: “He’s dead, Jim.”

Kirk: “Bones, do something!”

McCoy: “Sorry, Jim, there isn’t anything I can do.”

KirK: “Why?”

McCoy: “Because he’s dead.”

Kirk: “How do you know he’s dead?”

McCoy: “Because there’s nothing I can do.”

Kirk: “Because he’s dead?”

McCoy: “That’s right.”

Kirk: “But I was talking to him just one minute ago!”

McCoy: “Dammit Jim, I’m a doctor not a spiritual medium! I can’t bring back the dead anymore than I can cure a common cold.”

Spock: “Doctor, we could take him back to the ship, dissolve any blood clots, restore circulation, and restore homeostasis by molecular repair. He could fully resume duty within days.”

McCoy: “Spock, leave doctoring to doctors! What this man needs is a decent burial.”

Any similarity to persons living, dead, or merely not breathing is purely coincidental.