This article does not have any sources. (June 2009)
Cryonics is when people (or animals) are made very cold after a doctor says they are dead. When they are warmed again there might still be a cure for them because of better medicine that can be invented in the future.
Cold people like this are not awake at all as they have no brain activity. The law also says they are dead. Their body and its brain are made more like glass than ice because ice would harm their cells more. To do this, their blood is replaced with chemicals called cryoprotectants, which act like anti-freeze.
Making them cold can stop cells from dying but can kill many of them. Cryonics is not allowed unless you are already declared dead by law because this damage would make you dead by law. To be dead in that way means you cannot live with help from medicine we have today. The idea of people who do cryonics is that better medicine from tomorrow may be used for a cryonics patient, so the person may be alive in a different sense than the law uses today.
Cryonics is justified by three facts that are not well known:
- Life can be stopped and restarted if its basic structure is preserved.
- Vitrification (not freezing) can preserve biological structure very well.
- Methods for repairing structure at the molecular level can now be foreseen.
Cryonics should work, even though it cannot be demonstrated to work today. That is, the scientific justification for cryonics. It is a justification that grows stronger with every new advance in preservation technology.