Saturday, June 09, 2007

Rejuvenation Research Paper

My paper “Sufficiency, Justice and the Pursuit of Health-Extension” has been accepted for publication in the science journal Rejuvenation Research. The journal is “an international, interdisciplinary, peer-reviewed academic journal that covers all aspects of biology and biomedicine relevant to the combating, and ultimately the reversal, of age-related physiological and cognitive decline, in nonhuman species and eventually in humans”.

Here is a brief synopsis of the paper:

Should we, as a society, invest a greater amount of public funding into research projects that seek to better understand the aging process so that we can retard, and possibly even eliminate, aging? Let us call those who answer “Yes!” to this question those who support what we can call The Project. Of course those who count themselves as supporters of The Project will no doubt disagree with each other over many of the details of The Project. Such as its ultimate goal (e.g. compress morbidity or the elimination of senescence), how it can best be achieved, likely time-scales, etc. These finer details are all issues that I shall put to the side for the purposes of this paper. My primary concern is to critically examine the moral defensibility of one of the central assumptions which all proponents of The Project share. Namely that The Project is worthy of greater public attention and more public funding than it currently receives. To help make the case for this assumption more compelling I will refute what I take to be one the most formidable arguments against it. I call this argument The Justice Objection. When levied as a justice-based argument against The Project, The Justice Objection invokes more general considerations about justice that are consistent with what is called the Sufficiency View. This view maintains two theses (the first is a positive thesis, the second a negative thesis, Casal 2007): (1) justice requires we ensure that everyone rises above a certain threshold of welfare or wellbeing and (2) justice does not impose any distributive requirements beyond the positive thesis. By utilizing the tools of analytical political philosophy we can better understand what the Justice Objection is, and, most importantly, why it is mistaken.

The moral imperative to combat aging is an important, and challenging, applied topic that moral and political philosophers (as well as society in general) should take seriously. So I am very pleased about getting this piece into a science journal dedicated to these concerns. Many philosophers might not even contemplate submitting their work to journals outside of the discipline, either because they have an insular (perhaps even elitist) view of what research philosophers are suppose to do/ who their target audience should be, or they just assume (wrongly in my opinion) that journals in other disciplines would not be interested in hearing what philosophers have to say about these issues.

I think it is important to challenge traditional disciplinary boundaries, for this is necessary if we (i.e. normative theorists) hope to develop theories that can be applied to the real world. Furthermore, it is fascinating to see how other disciplines run their journals and the peer review process and to get feedback from referees in different disciplines. So pursuing interdisciplinary research has many benefits. Of course it is also challenging, as one must invest a good deal of their energies into keeping abreast of the empirical work being done on the relevant topic. And this requires one to exercise a different skill-set than that typically involved with pure conceptual analyses of values like liberty, equality and justice. And the latter, as I noted before, is the favourite pastime of most contemporary political philosophers.

I began seriously thinking about the moral imperative to combat aging about two years or so ago (and this event last year really spurred my interest, as I reported here). And when I teach my fourth year seminar “Genetics and Justice” we spend a few sessions on genetic enhancement. When raised with the prospect of combating aging students often express one (or both) of the following reactions: (1) how trite and trivial!(2)that is pure fantasy! My paper hopes to go some way towards showing why (1) is mistaken.

I believe (1) is mistaken for numerous reasons. Firstly, our societies currently spend an enormous amount of money trying to cope with the debilitating effects of aging. Aging has an enormous impact on the health of a population. It not only affects the wellbeing of individuals (making us more frail and susceptible to disease, causing loss of mental acuity, etc.), but aging also puts pressure on healthcare resources, has costs to our productive capabilities, etc. The stakes are thus very high. So the status quo is certainly not one that says “aging, how trite and trivial!”. All of us try (or at least should try) to retard the debilitating effects of aging by exercising, watching what we eat, etc. Should we not invest in biomedical research that could help us better promote the aims of extending healthy living? I believe we should. Such an aspiration is ingenious and noble, not trite or trivial.

So in this forthcoming paper I show how those who make The Justice Objection invoke an inappropriate principle (i.e. sufficiency) given the nature of the good at stake. When it comes to health we do not say that benefits to people above some threshold (like “normal functioning”) have no moral weight whatsoever. So while the sufficiency view may have some intuitive appeal when the good in question is wealth, it is not a defensible principle to invoke in the context of debates about health extension.

I do not address (2) in the paper but I want to offer some initial thoughts here. If those who say “Talk of retarding aging is mere science fiction” are implying that aging is an immutable process then they are simply wrong. (Of course if the question is- can we eliminate or even reverse senescence?- that is another matter). We already know that calorie restriction, for example, can influence the aging process. And cellular, molecular, and genetic studies of aging in in vitro models and in short-lived invertebrates have generated an impressive pace of discovery (E. Hadley et al., Cell 120, 565 (2005)).

If (2) is premised on skepticism that we may never be able to successfully intervene in our biology to retard aging (to any significant degree) then I think we need to take a “let’s wait and see” attitude rather than a dismissive stance. We are still in the very early days of the genetic revolution.

Those inclined to be skeptical should ask themselves how informed and consistent their skepticism actually is. For example, ask yourself if you think we will find a cure for cancer in this century? I certainly hope we will. And I believe we should invest in such research (even if there is no guarantee we will achieve that goal this century). The rapid progress that is being made with identifying the genes implicated in different diseases, and with experimental interventions like gene therapy, lead me to believe that significant breakthroughs will be made this century in terms of mitigating the natural lottery of life.

Of course it is hard to predict what will be possible, but I think there is a natural tendency to underestimate what we could accomplish. Just consider where science was back in 1907. And the progress we could make in the twenty-first century will no doubt dwarf the monumental gains made in the past century.

So now ask yourself the question: “Will we be able to successfully intervene in the aging process, so that we can live longer, healthier lives?” Again, I certainly hope so and there is some reason to believe that we could make some headway in this respect this century. The amount of funding we invest into understanding the biology of aging will determine how successful the endeavor to intervene in the aging process will be.

And it is important to realize that even just modest success would yield enormous benefits (something I think we often overlook). According to the authors of The Longevity Dividend, a modest deceleration in the rate of aging, sufficient to delay all aging-related diseases and disorders by about seven years, would yield health and longevity benefits greater than what would be achieved with the elimination of cancer or heart disease (32). So if you think eliminating cancer is a laudable aim, one should also believe that retarding aging by just 7 years is also a laudable aim. All else being equal, there is no moral difference between saving a life and extending someone’s life.

I myself am still working out the details of where I stand on many of these issues. As a prioritarian I believe benefits to those who are worse off matter more. And this is why my primary research has focused on gene therapy (rather than enhancement). However, as a pluralistic prioritarian I believe other things are important as well- such as the magnitude of the benefits of intervention (e.g. the number of disease-free years conferred), the likelihood and severity of the harm of non-intervention, etc. And senescence really complicates the story of trying to determine what the just course of action is, “all-things-considered”. We are all susceptible to aging, it increases our risk of disease and we know, with 100% certainty, that (barring intervention) it will eventually kill us if something else doesn’t first. There are a whole host of important and challenging issues here which moral and political philosophers should tackle.

Those looking for some good sources to read on these issues will find, in addition to the Longevity Dividend article by Olshansky et. al., Nick Bostrom’s "Fable of the Dragon-Tryant" and Aubrey De Grey’s "Life extension, Human Rights, and the Rational Refinement of Repugnance" of interest. And Rejuvenation Research has articles and interviews on these issues. For example, previous issues have featured interviews with Arthur Caplan and John Harris.