Mathematics of Physical Immortality

I don't want to achieve immortality through my work ... I want to achieve it through not dying.

—Woody Allen

Immortality is a tough subject to discuss. It is a word laced with many meanings, explicit and implicit. Interpretations of "immortality"—and reactions to discussing it, or even thinking about it—are affected quite severely by social context, politics, religion, philosophy, and other factors. So it's useful right out of the gate to have disclaimer.

Disclaimer: When referring to "immortality", I am most definitely NOT referring to Eternal Life, or anything even remotely like it. I'm not talking about spiritual blessings, gifts of god, supernatural powers, divine nature, the "quickening", magic, witchcraft, etc.

I'm just talking about not dying. I'd like to hope that anyone reading this is rational, regardless of their belief system, politics, or views on what a "natural" lifespan should be. Hence, I hope you can try to accept this very limited, rather plain definition of immortality, at least for the context of this discussion.

Outline
In this article, and the ones to follow, I will be discussing the mathematics of immortality, i.e., the mathematics of not dying a physical death. Here is a brief outline of how the articles will progress:

Introduction
This is what you are reading now. In addition to providing an outline of the series, this section will also provide a brief review of the difficult topic of death.

Discussing "Biological Immortality"
To do this subject justice, it will be broken into two parts:

The Gompertz Curve
I've discussed this subject before, but a refresher course may be in order. This is essentially the mathematics of aging.

Biologicial Immortality
I'll discuss a little of the math behind the term coined by Dr. Michael Rose. In addition, I'll tie the discussion in with SENS, the IBG, and the MPrize, and how these initiatives will be the first bootstrap to biological immortality. This will lead directly to the topic of longevity escape velocity.

Beyond Biological Immortality
This section seeks a more ambitious definition of immortality. Again, to do this subject justice, it will be broken into two parts:

Illustrating Immortality
Here, a couple examples will illustrate how we can, in theory, reach beyond the defeat of aging, to the defeat of death itself. Then a more practical example will revisit SENS as the first step towards not only longevity escape velocity, but the loftier goal of immortality escape velocity.

Inducing Immortality
The first two examples in the previous entry will illustrate a nice point, but examining the proofs, via mathematical induction, is a fun digression.

Practical Considerations
This section hasn't been written yet. As such, I may feel the need to break it down, as I did the previous two sections. Examples of practical considerations with mathematical underpinnings are population growth, boredom, methods of reducing death rates, etc.

Other "Practical" Considerations
This section hasn't been written yet, either. For now, the main practical consideration I know I'll be addressing is the conflict between an infinite lifespan and a finite existence: the crossing from Immortality to some semblance of Eternal Life. This section, very much unlike the previous ones, will finally cross the threshold from the mundane "immortality means not dying" to something far grander: the practical implication of living for an infinite amount of time. Let this serve as a teaser; as I said, I may break this section up into two or more parts, especially if I want to tackle the spiritual implications in a self-contained entry, so that the controversy can remain limited to that one entry.

Death and Life
Before we can talk about avoiding death, perhaps we should talk about death itself. Death has an interesting place in the world. It's ubiquity renders most people blind to it. And in many ways, death is necessary.

Death is what drives life, paradoxically. Death makes way for new life: without death, an exponential growth of life would cover the earth's surface and render it devoid of the very resources which make life possible. Without the death of the parents, there would eventually be no room for the children, or grandchildren, etc.

Life from Death
Furthermore, without death, life beyond the simplest of multi-celled animals could not exist. Plants can make their own food from photosynthesis, but large animals use too much energy to get theirs in the same way. Plants are sedentary in the extreme, using calories at a slower rate than an animal in a comatose state. It is only through such a low rate of metabolism that plants can get away with getting all their energy from photosynthesis.

But for animals, energy must be gotten in a more abundant form, and that form is chemical: carbohydrates, fats, and protein. Unfortunately, getting those nutrients means some other living thing must die. If not a whole organism, then at least some living portion of it.

For example, even if an animal eats an apple and spares the apple tree, the fact remains that the apple contained cells, and hence was alive. When eating the leaves off a tree, a giraffe does not kill the tree; nevertheless, the leaves were alive and must die for the giraffe to live.

To achieve the great diversity and beauty of nature, some animals even kill and eat other animals. Death makes life possible. The more death, the more diversity and beauty one can find in nature.

And in yet another quirk of life, portions of a living organism must die for it to live. For example, in humans, the cells lining the digestive track are constantly shed and replaced; dead skin cells constantly flake away, replaced from underneath; red blood cells only live for a few months before being recycled; precancerous cells die by the millions before one ever becomes a malignant tumor.

Intelligence from Death: Evolution
Another way that death is necessary to life, is that death drives evolution. On the one hand, without mutations, new, better-adapted traits could never enter a population. On the other hand, without death, those mutations would have a much harder time spreading across the population. Without death, the only way for a gene to spread to a larger and larger percentage of a population is for that gene to increase the fertility of the organism. Without death, mutations that reduce fertility (such as a reduced litter size, or a longer childhood before puberty, or more cells wasted on intelligence instead of being used for breeding) would never develop. Without death, mice would rule the earth, not men. Mice can outbreed us by a factor of 10,000 to 1. In fact, mice wouldn't even have developed, because smaller animals can breed even faster. Actually, animals would never have developed: bacteria are much faster breeders than the smallest of animals.

With death, however, mutations that reduce fertility, but increase resistance to death, can be selected for. Some examples of such mutations are those that make an organism bigger, stronger, or more intelligent; even flight is a trait that could never develop without death.

Intelligence from Death: Unsteady State
Even if you think that evolution is poppycock, consider that death is still necessary for the diversity of life. Even if you discount the need for mutations, you cannot discount the need for death.

Nature is kept in a delicate balance, often referred to as a "steady state". It's not completely steady: an especially cold winter might kill a large fraction of the vegetation in an area; then the small animals that feed on the vegetation will start to starve until their numbers are reduced enough that there is enough food left for the survivors. As the population of small animals declines, the population of larger predators will also decline due to starvation. However; in the following months or year (or years), the vegetation will be able to grow back faster than normal, due to the reduced population of small herbivores. Shortly thereafter, the increased abundance of vegetation will lead to increases in the population of small herbivores, and then the larger predators will increase in numbers as well.

It's never quite so simple as this, but the general idea is the same. A delicate balance is maintained, a sort of dynamic equilibrium. But without death, things would be quite different. The fastest breeders would quickly outnumber the larger animals. Had death ceased to operate in the world a century ago, the face of the earth would be covered with mice, bugs, and bacteria. Humans wouldn't be much more populous than they are now. Once again, without death, mice would rule the earth, not men.

Death and People
But this chain of the goodness of death is broken in humans. Just because the rest of nature has to die, why should we? The immediate answer one might come up with is because it's "natural", it's "the way things are." But humans are already above the rest of all life on earth: we are far more intelligent and resourceful. We have art, religion, politics, education systems, buildings, literature, etc. Some animals have the merest intimations of such grand artifacts: the beaver builds its dam; the spider builds its web; chimpanzees have enough intelligence to be taught a few hundred words in sign language, etc.

Is Death Natural?
But by and large, humans have lifted themselves up so far above the animals, that discussion of what's "natural" must be qualified three ways to Wednesday. (I have no idea what that means, but it sounds like "a lot". And I've heard versions with Tuesday or Sunday as well; there's probably a version for each day of the week. In which situations is a particular day appropriate for this expression?). After all, aside from herbal medicine prescribed by a shaman or "witch-doctor", all forms of medicine are "unnatural". Using electricity is unnatural. Wearing clothing is unnatural. Cooking food is unnatural. Reading and writing is unnatural. 99.9% of your everyday actions are probably unnatural. So as I said, "discussion of what's 'natural' must be qualified three ways to Wednesday."

So would it really be unnatural to try to conquer death? Doctors do it everyday, after all. Of course, a doctor only adds a few years to person's life, right? Well, what about children. A doctor that saves a child's life might add 70 or 90 years to that person's life. How is this different than a biomedical gerontologist adding 20, or even 50, years to a 60-year-old's life? Why is death natural for those who have lived many years, and unnatural for those who have lived but a few years.

Death Sucks
I could try to say it better than Phil, but I don't think I could. The following is excerpted from his extended blog entry entitled Death Sucks:

Mary ... posed the following question:

Why are you so scared of dying?

From the context, I'm going to assume that what Mary is asking is a philosophical question. She doesn't want to know why I would get out of the way of a speeding truck. All mentally healthy human beings are "scared of dying" in that sense; it's something we share with virtually every living being on the planet.

What Mary wants to know is this: why am I not resigned to my own mortality? Why would I want to engage in this unseemly practice of exploring alternatives to dying?

I'll tell you why, Mare.

Death sucks.

Some say that dying is as natural as being born. I say, so what? Vomiting is as natural as eating, but I happen to like eating a lot more.

…

Christianity (to use the religion I'm most familiar with) most assuredly does not teach [that you should be okay with the fact that you're going to die]. As C. S. Lewis famously put it:

But here is something quite different. Here is something telling me -- well, what? Telling me that I must never, like the Stoics, say that death does not matter. Nothing is less Christian than that. Death which made Life Himself shed tears at the grave of Lazarus, and shed tears of blood in Gethsemane. This is an appalling horror; a stinking indignity. (You remember Thomas Browne's splendid remark: "I am not so much afraid of death, as ashamed of it.)

I agree with Thomas Brown and with C. S. Lewis. I’m ashamed of death. Christianity teaches that death came to humanity as a result of our fall from grace. The history of technological and medical development shows that we die because we haven’t yet figured out how not to. Either way, death is a shortcoming. Either way, it’s evident that we were meant for something better.

Deep down, all human beings — including people of science, people of faith, and people who could care less about either — share the same natural revulsion for death. We can blot these feelings out and cover them up, but to do so is to become like those rabbits in Watership Down who sang melancholy songs while trading their lives for some lettuce and carrots.

Those who claim to have no fear of death, whether they be an Objectivist or the Dalai Lama or some Palestinian strapping dynamite to his chest, have lost touch with a primary truth of human existence: a truth which has lead us both to science and to faith. Those who seek to prolong human life — whether via antioxidants or cryonics or standard medical procedures — have tapped into that same fundamental truth: death sucks.

What Can We Do about It?
At this point, you might find yourself thinking, "So what? So death sucks! What can you do about it? Nothing! So why bother!"

But the thing is, we all can do something about it. We do something about it every time we look both ways before we cross the street. We do something about it every time we eat a healthy meal instead of an unhealthy one. We do something about it when we exercise and take our vitamins. We do something about it whenever we go to the doctor, whenever we get an expensive, but life-saving, medical treatment. We do something about it when we support cancer research or send a donation to the American Heart Association.

But some people are doing more than others. Some people advocate more money for aging research, and specifically for real anti-aging research. Perhaps "anti-aging" isn't even the right word, given how tainted it is by peddlers of skin creams and herbal supplements. What some people are advocating is research for "engineered negligible senescence": a true cure for aging, or at least a big step in that direction.

Live Long Enough to Live Forever
The sub-title to Ray Kurzweil's Fantastic Voyage was Live Long Enough to Live Forever. Regardless of your opinion of the merits or desireability of living forever, the premise is undeniably simple: you won't benefit from the medical technology that will be developed in the next 20-40 years, if you don't live that long first.

Living longer, even just a few years, could mean the difference between having access to a breakthrough medical treatment that will add 10-20 years to your life, or not having access to it. And that 10-20 years could be the difference between having access to the next big breakthrough, adding even more decades to your life, or not having access to it. In other words, losing 20 pounds and exercising three times a week could be all it takes to add 30 or 50 years to your lifespan. In fact, if medical progress is fast enough, losing those 20 pounds could be the difference between living to 65 or living to 165, or even 1,065.

So you see, there is something simple that almost all of us can do about blight of involuntary death. We can take care of ourselves.

Support Longevity Research
The other big thing we can do is to support the scientific and medical research of longevity. By doing so, we make life extending medicine available earlier, not just to ourselves, but to everybody. And by everybody, I mean everybody. Sure, these treatments will probably only be available to the rich in the beginning. But it was going to be that way anyway, whether these treatments were developed in 2030 or 2130. Sure, these treatments will only be available to the poor in third world countries a long time after they are available to the wealthy and middle class in the developed nations. But again, it was going to be that way anyway, whether these treatments reached the masses by 2060 or 2160. Bringing these treatments to fruition earlier makes them available to everyone earlier: earlier than they would have been available to them otherwise.

In the next ten years, we'll see a large number of charities and for-profit companies that we'll be able to support. For now, two big initiatives I'm aware of are the MPrize and the nascent Institute of Biomedical Gerontology (IBG). Both have great promise. Both aim to leverage the donations of the public into orders of magnitude more money spent on research.

The MPrize
The MPrize accomplishes this through three large indirect routes. First, a research prize often generates at least 10 times more money spent on research than is offered in the prize. Second, the prize is generating publicity as it grows, which leads to further donations. The faster the prize grows, the faster this snowballing effect can work. In other words, money you donate today will not only be used for the prize, but it will help generate future donations as well. Third, the program of The Three Hundred aims to leverage the future donations of donors today, ensuring that the prize will continue to grow, and helping less-than-wealthy individuals to donate the equivalent of $10,000 or more, through smaller annual donations of $1,000.

The IBG
The IBG aims for a loftier goal, but as such, it is not quite as well leveraged. The money that goes to the IBG will be directly spent on research, rather than encouraging others to do the research. This difference means that the IBG loses one of the three advantages of the MPrize, namely the 10x or greater monetary leverage that research prizes can often generate.

However, what the IBG lacks in monetary leverage, it will make up for with focus. The IBG will seek to implement a very focussed set of strategies, the Strategies for Engineered Negligible Senescence. These seven strategies will probably not cure aging. But that's not the point. The IBG doesn't need to cure aging: it needs to buy us time. If the IBG could develop therapies that add 20-30 healthy years to the aging Baby Boomers' lives, then that 20-30 years would buy those people 20-30 years to wait for the next generation of anti-aging therapies. And with 20-30 extra healthy years, those Baby Boomers would see the possibilities of further life extending medicine. Medical research money would begin pouring in by the billions. In this respect, the IBG benefits from the second advantage of the MPrize: snowballing donations. Only instead of donations snowballing from the publicity of a rapidly growing prize, it would be billions (or tens of billions) of dollars in state funding snowballing from the results of the research funded by the IBG.

The Mathematics of Immortality
But where is all of this going? In the next few installments, I will discuss the mathematics of immortality, showing that living longer now is worth it in the long haul. It will also show how a few dollars donated to either of the above initiatives could save more lives than you could ever hope to save by just about any other route.

Read Full Story