A recent NYT book review:

In his new book, “Long for This World,” Weiner makes similar use of another brilliant theoretical scientist, the English gerontologist Aubrey de Grey, a tireless proselytizer for radical life extension. … The inspiration for de Grey’s scientific quest for immortality came in a flash one sleepless night: “What these [aging] troubles all have in common is that they fill the aging body with junk. Maybe we can just clean up all the scree and rubble that gathers in our aging bodies.” The beauty of this view is that “curing” aging requires no special knowledge of design, or any understanding of just how the cellular junk got there in the first place. It only requires that we get rid of it. As de Grey sees it, there are seven types of cellular junk. … De Grey’s dream of conquering death may seem far-fetched and unreal, but Big Pharma is already at work on some of these ideas. …

As Weiner points out, there is a big problem with immortality. Traditionally, we have viewed our lives as unfolding in stages: … Immortality could wind up being a terrible stasis. “A huge part of the action and the drama in the seven ages comes from the sense of an ending, the knowledge that all these ages must have an end,” Weiner writes. We might live forever in a state of unending boredom. And the technology might benefit the wrong people: … Mao Zedong might still be alive.” … My patients were dying young and felt cheated out of their best years. They did not want immortality, just the chance to live the life span that their peers could expect. What de Grey and other immortalists seem to have lost sight of is that simply living a full life span is a laudable goal.

As with cryonics, a proposal to extend life substantially is greeted with bizarre concerns about living too long, or the wrong people living longer. Why not apply such complaints to ordinary medical gains?

A big part of the problem, I think, is that talk of “immortality” invokes an extremely far view. But finite increases in lifespan really have little to do with immortality. Immortality means you never die, ever. But forever is a really really long time! In fact, nothing you can imagine is remotely as long.

De Grey seems to be part of the problem here. Some times he say things like:

I have a lot of problems with the use of the word immortality to describe what I do because it’s taken by religion. Immortality means inability to die; it means inability to actually be killed by anything, and I don’t work on that. I work on stopping people from getting sick. I do not work on stopping people from being hit by trucks.

But if you search for his name and “immortality” you will find he is associated with that word quite often, including in the title of many interviews of him.  He’s even listed as an advisor to the Immortality Institute. And you’ll find things like:

De Grey says he is talking about the “indefinite extension of longevity.” “Average life spans would be in the region of 1,000 years,” he says. “Seriously.” … So humans will be just as spry at 500 as we were at 25? “If you have difficultly imaging this, think about the situation with houses. With moderate maintenance they stay up, they stay intact, inhabitable more or less forever. It’s just that we have to do a bit of maintenance to keep them going. And it’s going to be the same with us,” says de Grey. …

“The first generation [of new med tech] will give us maybe 30 extra years of healthy lifespan,” says de Grey. “So, beneficiaries of those first therapies will still be around to benefit from improved therapies that will give them another 30 or 50 years and so on. So this is basically staying one step ahead of the problem.” … De Grey acknowledges that immortality will not be cheap. “We are talking about serious expenditure here.”

Are houses immortal? Very few (no?) thousand year old houses still function, and maintenance costs probably makes them cost more overall than just building a new house. Old houses are even more expensive if you want to retrofit them with modern conveniences, such as lights or air conditioning, or if you consider the opportunity cost of the land on which they sit. And even if, with sufficient expenditure, houses could last a thousand years, that should be little comfort to those who can’t possibly afford such expense. Furthermore, lasting a thousand years is nothing like being immortal!

A thousand year lifespan would be fantastic, relative to our lifespan. I want it! But it is nothing like immortality. It would have clear stages, and a very real end to anticipate. Anyone with a halfway decent imagination couldn’t remotely run out of new interesting things to do, places to visit, people to see, etc. Yes they’d have time for twenty times as many careers, hobbies, marriages, and vacations as we do now, but it should only take a moment’s reflection to realize you there are far more than twenty times as many things to do than we manage in our lives. For example, any decent library holds twenty times more books than you’ve ever read.

Yes it may be logically possible to live forever, and yes you can’t do that if you die now, so not dying now keeps open that logical possibility. But I expect each new scale of lifespan to offer new novel, difficult, and expensive obstacles to living that long.  If you agree, you should seriously doubt your ability to keep beating such odds forever.

Yes, keep trying to live if you love life, and rage, rage against the dying of the light. Do better; live longer. But why confuse everyone by talking as if you expect to achieve the literally infinite success of “immortality”? It is fine to say “let’s extend lives as much as we can.” But must you really talk as if nothing less than infinite success will do?  Can’t you see that makes you sound rather crazy?