Progeria is a disease generally referred to as “premature aging.” Children afflicted with this terrible genetic condition are cursed to short lives, tortured by symptoms that look remarkably like advanced age. In fact, while it might seem simple-minded to say that progeria “ages” its victims, the metaphor actually holds up quite well on the cellular scale. Looked at from the opposite direction, consider the case of a man unchilled after a century in cryogenic suspended animation; is he really more than a hundred years old, if his cells didn’t progress a day while he was under? There are fuzzy definitions at work here, contradictions where we want to age children with progeria according to the time they’ve been alive, and the users of cryogenics according to progression of their biological development. In general, we colloquially view age from the perspective of the mind; what unites these two objections is that they put the emphasis on the amount of time experienced by the conscious mind.

Despite its best efforts, science really can’t come up with anything better. Its definitions for age are couched in much more technical terms, and occasionally make a quantifiable claim about reproductive capacity and genetic integrity, but for the most part these definitions are as full of holes and glaring exceptions as any explanation from the popular culture. We’re not even entirely sure that aging is necessary, as we examine so-called “immortal” cancer cells and manipulate stem cells with increasing skill. Immortality seems, if not plausible, than at least a phenomenon worthy of inspection.

There are few themes that have dogged the visionaries of speculative fiction more than the quest to cheat death. Even that terminology is revealing, implying that life extension is some pilfering of death’s rightful commodity. Life extension is the materialist’s version of Dr. Faustus’ ill-fated agreement, science standing in for demon worship as we strive for the ultimate forbidden fruit. That was always how it was framed: in fiction, our attempts to find a loophole in nature’s ultimate law are universally disastrous, pacts with dark sciences that wreak havoc on the world, or which hollow out their users in some fundamental way.

And yet, modern medicine is already estimated to increase the average human lifespan by as much as a year, every five years. To the radical life-extension set, the “Methuselarity” crowd, that means we’re one fifth of the way to our goal. Pull that figure up to one-per-one, we’ll obtain immortality.

Next page: Why do we age?