There are various competing strategies how to achieve meaningful life extension or rejuvenation, including , but not limited to, genetic manipulation, periodical elimination of damage, caloric restriction,  molecular nanotechnology and mind uploading. A useful review of these strategies has been published in the book The Scientific Conquest of Death: Essays on Infinite Lifespans (2004) by the Immortality Institute. Most people will recognize that these strategies are not mutually exclusive. Some of them can be practiced right now (e.g., caloric restriction) and others ( e.g., periodical elimination of damage) could serve as a bridge to more comprehensive interventions such as a comprehensive genetic overhaul of human biology. As has often been recognized on this website, cryonics holds a special place among life extension strategies because it enables one to benefit from progress in the biomedical sciences that may not occur during one’s lifetime. We would like to think we can escape death by jumping from one successful biomedical innovation to another and that, of course, all the good things will happen in our lifetime, but reality often interferes with such optimism.

One thing that might greatly accelerate the pace of progress in the field of longevity science is the development of an integrated framework that studies the logical and empirical relationships among all these strategies. For example, a recent blog entry on the technical challenges surrounding chemopreservation of the brain triggered a meaningful private exchange about issues concerning the perfusion of ischemic tissue, empirical criteria for information-theoretic death, and the options for histological validation of cryonics technologies.  Such overlapping areas of investigation are plentiful and it would be helpful to explicate them.

Too much focus on “the big picture” can interfere with the identification of original ideas and rapid progress. Too little attention to the adverse effects of compartmentalization risks the waste of resources, which is not a trivial concern in the still poorly funded life extension community.

Reducing compartmentalization can have other sobering effects as well. For example, it is not unusual to see a group of researchers advocating a new approach to their field that is routine in other areas of investigation. For example, the idea that anti-aging research could benefit from less emphasis on illuminating the exact molecular mechanisms of aging and simply treat the observable manifestations of aging is no news to researchers in the field of cerebral ischemia. The pathophysiology of stroke is so complex that greater progress could be achieved by identifying clear targets for pharmacological intervention. But after decades of research it has become abundantly clear that such a paradigm change is no guarantee for more rapid progress. Despite this goal-oriented approach not one single neuroprotective agent has survived clinical trials.  This does not mean that such pragmatic approaches should be abandoned. It does mean, however, that research ideas should be evaluated on their empirical success and not just on their logical merits.

There are obvious examples where the claims in one field seem to make the claims in another field redundant. The most obvious example is the case of molecular nanotechnology. The projected timescales that are envisioned for this technology are not much different from the timescales that are envisioned by some anti-aging researchers to develop meaningful rejuvenation. In that case one could argue that (exclusive) preference should be given to those research programs that allow for the most comprehensive manipulation of biology. For example, a mature nanotechnology would be able to rejuvenate people, resuscitate cryonics patients, and alter the human endoskeleton to make us far less prone to fatal accidents. Such an argument would be a logical extension of the argument against devoting too much time to find treatments for specific age-related diseases instead of tackling aging itself.  Similar reasoning can be employed against anti-aging research. If accelerated change will bring the prospect of general molecular control within reach in the next few decades it makes little sense to spend vast amounts of time agonizing over specific anti-aging interventions. Why not just launch a “Manhattan Project” to pursue the much more comprehensive vision of molecular nanotechnology?

From a logical point of view, this is a persuasive argument. The limitations of such a perspective should now be obvious too.  We do not have certainty about the future of technological progress, let alone its specifics. As a matter of fact, in such matters it is not even evident how we should think about statistical or inductive probabilities.  To some people, the progress in one field is indicative of the progress we are going to observe in other fields, including fields in which there has been little progress to date. The problem with such naive inductivism is that it can just as well be used to  make the opposite case if a different reference class is chosen.

The logical empiricist philosopher Rudolf Carnap once wrote:

The acceptance or rejection of abstract linguistic forms, just as the acceptance or rejection of any other linguistic forms in any branch of science, will finally be decided by their efficiency as instruments, the ratio of the results achieved to the amount and complexity of the efforts required. To decree dogmatic prohibitions of certain linguistic forms instead of testing them by their success or failure in practical use, is worse than futile; it is positively harmful because it may obstruct scientific progress.

A related argument can be made about the science of personal survival. We should be cautious about privileging any line of research on  “logical” grounds. The fate of competing visions should be decided through empirical investigation.  This position should not be interpreted as saying that there is no place for logic in choosing research programs.  Logic has a central place in research design and interpretation of experimental observation but it cannot be solely relied upon a guide for decision making. Empirical observation disciplines thinking and ample room should be left for the unexpected. As Nassim Nicholas Taleb has pointed out:

There is a lot more randomness in biotechnology and any form of medical discovery. The role of design is overestimated. Every time we plan on trying to find a drug we don’t because it closes our mind. How are we discovering drugs? From the side-effects of other drugs.

Many experimental researchers have had the experience of engaging in research to find a solution to one problem but to discover the solution to another problem instead. Researchers who have recognized and embraced this phenomenon by becoming less fond of their own ideas and more open to run with such unexpected discoveries have reaped great benefits.

Most contemporary philosophers and social scientists have little interest and understanding of logic or the physical sciences and  therefore have little to offer to those who want to understand the philosophical aspects of knowledge. The following five books have been written by thinkers who have a great respect for science and the importance of empirical observation. With the exception of one book, no 21st century thinkers are featured to ensure that hype is not mistaken for importance.

(1) Hans Reichenbach’s The Rise of Scientific Philosophy (1951) is one of the best 20th century books on philosophy. The author shows how speculative and rationalist philosophy has been gradually replaced by the natural sciences. Writing from a consistent empiricist perspective, Reichenbach proposes that the lack of progress in philosophy is due to philosophers asking themselves questions that could only have been answered by the experimental method and the tools of modern logic. In the chapter about induction Reichenbach answers David Hume’s skepticism about causality and proposes a pragmatic justification of induction.

(2) Alfred J. Ayer’s Language, Truth and Logic (1936) is a classic and accessible exposition of logical positivism (or logical empiricism) by an English philosopher. Logical positivism is a school of thought in philosophy that is strongly shaped by the advances in physics and mathematics and seeks to eliminate metaphysics and meaningless statements from philosophy. Like most other philosophers in this tradition, Ayer kept refining his views throughout his life but always remained committed to the objectives of the original Vienna Circle.

(3) Rudolf Carnap was the most important exponent of logical positivism but his writings are of such an abstract and technical nature that most fellow philosophers and scientists are only familiar with his early popular statements of the positions of the Vienna Circle. A notable exception to his demanding work is his book An Introduction to the Philosophy of Science (1966) which is based on a seminar Carnap taught on the philosophy of the physical sciences. This book is not only valuable for its rigorous treatment of the philosophical foundations of physics but also represents a good summary of the views of the late Carnap.

(4) Bertrand Russell is among the most popular philosophers of the 20th century and had little reservations about speaking his mind on topics ranging from atheism to marriage. Unlike most philosophers that work in the analytic tradition, Russell had a great interest in the history of philosophy which would find its destination in his monumental and rich A History of Western Philosophy (1945). Russell attempts to treat the thinking of most philosophers he discusses with respect but the mindset of a logician and scientist is ever present, making this book one of the few available histories of philosophy from a (sometimes reluctant) empiricist perspective. The book does suffer from Russell’s highly subjective approach in some chapters, notably his rather melodramatic treatment of Friedrich Nietzsche.

(5) Nassim Nicholas Taleb’s Fooled by Randomness: The Hidden Role of Chance in Life and in the Markets (2001) is not a book on philosophy but the general approach that informs his book about the role of chance in life and markets is informed by a thorough skepticism about our claims to knowledge. As a “skeptical empiricist” Taleb stands bemused at the urge of humans to seek and detect patterns everywhere and our illusions about control. Taleb’s work received a lot of well deserved attention after the 2008 financial crisis but his distinct epistemological views still receive little attention.

popperThe philosopher Karl Popper has published on a wide variety of subjects but his most lasting contribution is his answer to the problem of induction by drawing attention to the asymmetry between verification and falsification. A theory can never be proven, but it can be falsified. Popper’s falsification criterion can also be used  to distinguish scientific theories from unscientific theories. His ideas on science and knowledge are captured  by his philosophical perspective called critical rationalism.

One does not necessarily have to be an avid reader of Popper to be a critical rationalist. As a matter of fact, some people are critical rationalists by temperament. They have an open mind, encourage critical thinking, and are suspicious of any claims that something is “certain” or “settled.” Unfortunately, one can also subscribe to critical rationalism as a philosophical perspective and be a self-righteous arrogant bastard at the same time, such as…..Karl Popper.

One of the great ironies in the history of thought is the disconnection between what people preach and what they practice.  In Fooled by Randomness, Nassim Nicholas Taleb writes how members of the Vienna Circle tried to avoid Popper, “not because of his divergent ideas, but because he was a social problem,” being “a terrible listener and bent on winning arguments at all costs,” according to people who knew him.

Even a casual acquaintance with his writings is sufficient to detect this trait. His self-righteous character is not only evident in his thinking about social philosophy and politics, it permeates his writings about epistemology and science as well, as can be seen in his strong obsession with his own place in the history of thought and his recognizable belligerent style.

Although Popper has become known as a fierce critic of authoritarian social thinking, utopian plans to reform society and an advocate of the “open society,” his writings on political matters display the spirit of a rabid Jacobin, throwing around words such as “catastrophe,” “nonsense,” “irresponsible,” “evil,” and “absurd” like there is no tomorrow. Despite  his “anti-authoritarian” perspective on politics, Popper routinely descends into handing down all kinds of dictates about how to organize society.

Some people have drawn attention to the tensions between Popper’s epistemology and interventionist views. The social philosopher Anthony de Jasay carefully reviewed Popper’s problematic arguments for “piecemeal social engineering” and democracy in his insightful essay “The Twistable is not Testable: Reflexions on the Political Thought of Karl Popper.” It may not come a surprise that Popper’s writings have been employed to advocate the most grandiose plans to remake the world.

Taleb observes that “we like to emit logical and rational ideas but we do not necessarily enjoy this execution.” Reading Popper can be a rewarding experience, but it is not necessarily a pleasurable experience…..