The concept behind immortality through cryonics goes something like this: If you have yourself frozen immediately after you’ve died, doctors in the future might someday have enough knowledge to repair the cell damage that led to your death. If they fix what killed you, they might be able to reanimate you, because your cells have been preserved. In an extreme view, medical science might even someday be able reverse the symptoms of aging, meaning you could die an old woman and come back as a teenager. These claims are made by the Web site for one company that has put many hopeful people into cold storage.

It’s not that simple, though. No human being has yet been reanimated. One complicating factor is that when your body cells freeze, water leaks out of them and collects in the spaces between them. The ice crystals that form can puncture the cell membranes. So, in addition to having to cure whatever killed you, science of the future will also have to have miniature robots travel inside your body to repair the ice damage.

(A newer process called vitrification freezes without producing these damaging ice crystals, according to the Web page of Alcor, one of the leading cryogenic companies.)

Sounds like science fiction, and most scientists would agree that it is, but it’s probably worth remembering that scientists currently freeze human embryos and successfully implant them later. My dog, Lucia, plays with one of these thawed “totsicles” regularly.

Since 1967, when James Bedford became the first person to undergo cryogenic suspension, at least dozens of people have paid tens of thousands and up to have their bodies (or, if they’re on a budget, just their heads) frozen.

Blame it on your karmic curse
Oh shame upon the universe
It knows its lines
It’s well rehearsed