About Rationally Speaking

Rationally Speaking is a blog maintained by Prof. Massimo Pigliucci, a philosopher at the City University of New York. The blog reflects the Enlightenment figure Marquis de Condorcet's idea of what a public intellectual (yes, we know, that's such a bad word) ought to be: someone who devotes himself to "the tracking down of prejudices in the hiding places where priests, the schools, the government, and all long-established institutions had gathered and protected them." You're welcome. Please notice that the contents of this blog can be reprinted under the standard Creative Commons license.

Saturday, May 04, 2013

Moore’s law and the origin of life: a study in demarcation

by Massimo Pigliucci

My most recent post was about the worthiness of so-called “demarcation” problems, such as reflections on what distinguishes science from philosophy, the latter from theology, and the former from pseudoscience. My interest in this field has been rekindled because of a long time collaboration with my colleague Maarten Boudry, which has resulted in a forthcoming edited book on the topic, to be published in July by Chicago Press.

Here I want to move from the broad overview I gave last time to a specific recent case at the borderlands between science and pseudoscience: Alexei A. Sharov and Richard Gordon’s paper “Life Before Earth,” currently unpublished but in preview at Cornell’s arXiv. PZ Myers has already harshly commented on the paper, clearly relegating it to the dustbin of pseudoscience. While I don’t disagree with PZ’s overall assessment, I think it is instructive to get a bit deeper into it and unpack the reasons for such judgment. After all, Sharov and Gordon are actual scientists (the first at the National Institute on Aging, the second at the Gulf Specimen Marine Laboratory), and the paper has all the appearance of legitimate, if boldly out of the mainstream, science. (Of course the fact that it hasn’t been published, yet, in a peer reviewed journal is an issue; but it’s not like there is no garbage being published by legitimate scientific journals anyway.)

To begin with, it is not entirely clear what the Sharov and Gordon paper is actually about. Yes, their main claim appears to be that one can use Moore’s so-called law (actually a straightforward empirical generalization based on a very specific data set), a linear relationship between CPU transistor counts and their dates of introduction, and apply it to the problem of when life might have originated in the universe. Here is the stunning claim made by the authors as a result of their exercise: “Linear regression of genetic complexity (on a log scale) extrapolated back to just one base pair suggests the time of the origin of life = 9.7 ± 2.5 billion years ago.” This would be stunning, if true, for the simple reason that earth itself is only 4.54 billion years old, which would therefore squarely place the origin of life in some other region of the cosmos.

Before we get to the meat of Sharov and Gordon’s claim, however, it is worth noting what is so confusing about the paper in the first place. Their main result is presented in Section 1 of the 26-pp. long work, with much of the rest devoted to tangentially, or not at all, related points about which the authors provide an odd mix of a meager overview of the literature and their (largely unsubstantiated) personal opinions. For instance, Section 2 deals with the variability of the rate of evolution as well as Gould and Eldredge’s famous theory of punctuated equilibria. While Sharov and Gordon do need to reassure their readers that their proposed trend of increase in genomic complexity isn’t undermined by too wild fluctuations of said rate over geological time, this has actually little if anything to do with punctuated equilibria, which is a theory about morphological evolution, which has been applied so far only to a relatively small subset of biological taxa.

Section 3, addressing the question of why genomic complexity (allegedly) increased exponentially during the history of life on earth is highly speculative to say the least (invoking concepts such as “evolution as cascading emergencies”), not to mention extremely brief.

Section 4 addresses the almost comical question of whether life could have originated from a single nucleotide (a bit of genetic information). Most practicing biologists would answer “hell no” to that question, but Sharov and Gordon treat us to a highly idiosyncratic (and even more debatable) tour of origin-of-life theories, including the RNA world, the idea of Graded Autocatalysis Replication Domains, the theory of autocatalytic reactions and so forth. Interesting, highly speculative, marginally relevant.

Section 5 is yet another, more in-depth, detour on hypotheses that tackle the problem of going from (very speculative) early surface metabolism (i.e., heritable metabolic systems that allegedly evolved on mineral surfaces) to the RNA world, and finally to the evolution of the first cells. Add some additional speculation on LUCA (the Last Universal Common Ancestor of all life forms on earth), and you can move to Section 6, addressing the question of how life can possibly survive in the interstellar void.

This is of course necessary because if life originated before earth did, then it follows that some sort of panspermia-type hypothesis must hold: life got started somewhere else, and then somehow made it to the third planet in our solar system. Needless to say, this bit of the paper is also highly speculative, having to do with the possibility that the solar system got its building materials from the explosion of a nearby star, for instance. Moreover, the authors bring up the discovery of bacteria that survived in ice for 750,000 years as if that were a reasonable approximation to millions of years of existence in the interstellar void, and so forth.

We then move to Section 7 of the Sharov and Gordon, where they explore the implications of a cosmic origin of life, speculating (wildly) that eventually we may be able to reconstruct a single evolutionary tree elucidating the phylogenetic relationships between terrestrial and extraterrestrial bacteria (never mind, of course, that no sample of the latter is in sight, at the moment...). Interestingly, the authors come down against the idea of “intelligent panspermia,” i.e., the possibility that life on earth (and other planets) was seeded on purpose by extraterrestrial intelligent beings. How do they know that? They confidently state that the evolution of intelligence requires 10 billion years, though we are not told how they arrived at such a bold and confident conclusion. In the same section the authors also manage to trash the famous Drake equation (one of the few theoretical foundations of the SETI program), and to answer the infamous Fermi paradox: the reason we haven’t heard from other intelligences in the universe is because we are likely the first one to appear on the block.

[Incidentally, and disturbingly, a good number of the references given in the paper are to Wikipedia entries! Not exactly the highest standard of scholarship I can think of.]

Section 8 deals with the lagging of genetic complexity when compared to the complexity of the mind. What does that have to do with the only original point of the paper (remember? The one about Moore’s law and the timing of the origin of life)? Not much, but what the hell. Here we find claims such as that humans are “superior” (not an evolutionary term) to mice (I guess these guys never read The Hitchhiker’s Guide to the Galaxy), and that languages too evolve following Moore’s law: did you know, for instance, that Chinese went from 2,500 characters 3,200 years ago to 47,000 characters today, which yields a “rate of language doubling time” (huh?) of 825 years, which in turn “exceeds the rate of brain increase in evolution by a factor of >3000”? Wow. Meanwhile, of course, romance languages haven’t evolved much, despite their ability to produce Shakespeare, or the Sharov and Gordon paper...

But wait! We ain’t done yet! Section 9 goes on to extrapolate the growth of complexity into the future, because extrapolating it back to the past isn’t a hazardous enough practice. To their credit,  Sharov and  Gordon dismiss Ray Kurzweil’s ideas about a forthcoming “technological singularity,” though they do so not based on the incoherence and lack of empirical support of the concept, but rather on the rather simplistic assumption that, you know, humans will always be in control of the power grid, so all we need to do to stem the onslaught of the Cylons is to pull the plug...

The last, tenth, section of the Sharov and Gordon paper has to do with a “biosemiotic perspective” on things, that is with the standpoint that considers living organisms qua agents. From there the authors immediately slide into semi-incoherent talk of reintroducing goals and meanings in the natural sciences, give a completely irrelevant nod to my own field of phenotypic plasticity studies and promptly quit.

All of the above doesn’t quite cross into pseudoscience, though it skirts perilously and repeatedly near that fuzzy borderline. A charitable reading of it is that the bulk of Sharov and Gordon’s paper is a somewhat disjointed, highly speculative tour de force of the field of origin-of-life and (somewhat) related studies. But what about the core of their manuscript, Section 1?

Well, the first highly questionable statement there is that “the core of the macroevolutionary process ... is the increase of functional complexity of organisms.” No, it isn’t. Stephen Gould long ago persuasively argued that there is no necessary direction of increased complexity throughout evolution. The only reason why complexity historically follows simplicity is because life had to start simple, so it only had “more complex” as a direction of (stochastic, not directed) movement. It’s a so-called “left wall” effect: if you start walking (randomly, even) from near a wall, the place you end up is away from the wall. And of course, as Gould again pointed out, life on earth was (relatively) simple and bacterial for a long, long time — and none the worse for it either. Moreover, the most complex organism on earth — us — though very successful in certain respects, is actually a member of a very small and often struggling group of large brained social animals. Measured by criteria such as biomass, bacteria still beat the crap out of us “superior” beings.

But the real problems begin for the Sharov and Gordon paper when they finally get to the business at hand: correlating genomic complexity with time of origin of the respective organisms, and then extrapolating back in time. [As a commenter on my Twitter stream pointed out, they could just as “reasonably” have extrapolated into the far future, arriving at the conclusion that the entire universe will eventually be made of DNA...]

The authors realize that simple genome length won’t cut it, because what matters is functional complexity, and there are some portions of the genomes of various organisms that are redundant and possibly without function. Nonetheless, they end up plotting the log-10 of genome size against time, which is how they arrive at the figure of 9.7 billion years ago for the origin of life. As PZ Myers quickly pointed out, however, even if we accept the procedure at face value, they simply cherry picked the data: plenty of organisms that don’t show up on the graph (plants and fungi, for instance) would completely scramble the results. Make no mistake about it: this is a fatal blow to the entire enterprise, and one that the authors ought to have thought about well before posting the paper.

The second fundamental problem, of course, is with Moore’s law itself: as I mentioned at the beginning, it was derived empirically from a very specific data set having to do with a particular type of human technology. There is no reason on earth (or beyond it!) to assume that the “law” (actually, a limited empirical generalization) should hold for measures such as genomic complexity, or for natural phenomena that are not of human origin.

Lastly (third fatal blow), the problem is with the procedure of statistical extrapolation itself. It’s very useful, of course, but it needs to be deployed with much caution. As anyone taking a Stat 101 course soon learns, data interpolation (i.e., curve fitting within the available range of data points) is a very effective and reliable technique to predict “missing” data; but extrapolation (i.e., extension of the curve fitting beyond the available data range) is a tricky business. Unless one is very confident that whatever mechanism underlies the relationship among the data actually holds regardless of range, one is on very shaky ground. Take, for instance, the most common curve fitting exercise in biology: the one relating the rate of growth of a population to time. If we start, say, a culture of bacteria with fresh growth medium, the colony will initially follow an exponential curve; if we extrapolate this curve a bit into the future, though, we arrive at the nonsensical prediction that the colony will soon take over the entire planet. It doesn’t. Why not? Because resources are limited and because there is going to be competition to acquire them from other species. Which is why many biological populations actually follow a logistic growth curve: they start out exponentially, then begin to slow down, and eventually reach an equilibrium determined by environmental constraints (the so-called carrying capacity in ecology). More complex dynamics (some actually leading to extinction) are possible too, but the point is that an ecologist who took seriously the initial exponential growth and used it for predictions in a scientific paper would be a fool to be laughed out of court immediately. Sharov and Gordon give us no reason to take their extrapolation backwards in time any more seriously.


  1. Awesome analysis. Are you saying that this is science because it presents a testable hypothesis, even if the empiric analysis upon which they base it is loose and flawed? Could it inspire serious scientists to more effectively explore origins in similar way that the clearly preposterous "spooky action at a distance" inherent in Newton's gravity inspired Einstein?

    1. Tony,

      > Are you saying that this is science because it presents a testable hypothesis, even if the empiric analysis upon which they base it is loose and flawed? <

      Not sure it is science, actually. I consider this to be a genuine borderline case. At the moment it hovers somewhere between sloppily done science and downright pseudoscience. But some clever person may figure a way to pull it all the way on this side of science land one of these days.

    2. A nice lesson in how not to do science Massimo. You can call it pseudoscience, however, the assumptions made by the authors (i.e. evolution moves in the direction of complexity – I like Gould’s analogy about the wall, you can take a function that nicely describes a very specific application and assume it'll work for the origin of life, and without a means of verifying your assumption you can just extrapolate backwards in time and it'll work) are nothing short of incompetent. It's like these guys were out drinking beer and talking about this. And the more they laid it out, along with the more beer they drank, the more brilliant the developing theory sounded. The next day, ignoring their critical sensibilities, that should have told them this is ridiculous, they published it.

  2. Back when I was doing genetic programming & artificial life, there was the matter of evolution rates related to populations sizes and other factors. I don't know if any Moore's Law has come into this, but it might be interesting to see.

    But at least this paper doesn't have any "intelligent design" in it.

  3. As I see it the science/pseudoscience debate is a philosophical debate and clearly is not an issue for science. And I pretty much agree with Susan Haack’s perpective.

    Anyway I agree that it is quite healthy that the mainstream ideas must be challenged, and on this matter, some time ago I found a very interesting view on this issue by Freeman Dyson:


  4. There is science and non-science, and then there is simply bad science. I think in this case, seen in isolation, it is the last of the three. It becomes pseudoscience when they have been shown that they are wrong and start with confirmation bias and the moving of goalposts.

    The same for Intelligent Design, by the way: That idea, in isolation, could be scientific. One could find a planet in orbit around a distant star one day that has complex life but no fossil record, and the organisms on it show no phylogenetic structure, no vestigial organs, etc. In that case, it would surely be at least a possibility that that biosphere might have recently been created by some currently unknown alien intelligence for currently unclear reasons because otherwise we would expect to see fossils and phylogenetic structure.

    What makes ID pseudoscience is that the idea contradicts masses of evidence but its proponents fail to acknowledge that fact.

    1. I'm not aware of any evidence that specifically *contradicts* ID.

    2. Okay, I could have put that better. There are masses of evidence that make more sense under the assumption that life evolved than under the assumption that it was intelligently created. Unless ID moves the goalposts back to an appeal to the mysterious (who knows why the designer might have preferred to build the recurrent laryngeal nerve like that?), in which case ID-life would be indistinguishable from evolved-life, in which case evolution is the more parsimonious assumption because it contains one superfluous entity less. Better?

  5. This is what defines pseudoscience for me: Any "theory" that introduces the nonmaterial. (Another word for 'nonmaterial' is 'magical'.) Intelligent Design is a great example of pseudoscience.

    For example, string theory and M-theory are materialist theories, so they are not pseudoscience. One might call such theories "edge" (as in "cutting edge") science, though. Another example is the hypothesized WIMP (Weakly Interacting Massive Particle) theorized to explain dark matter. No conclusive evidence yet has been found for WIMPs. It may be edge science, but it is clearly not pseudoscience.

    A materialist theory may appear to be crazy, and may even turn out to be flat wrong (as could be the theory presented in the paper being reviewed above), but it is not pseudoscience.

    1. The paper Massimo is referring to seems (just on basis on Massimo and Mayers comments, I didn't read it) a case of plain speculation (scientif, non-scientific or pseudoscientific, ...). But how to categorize more conventional and respectfull issues such as the Einstein's cosmological constant (long ago acknowledged as a mistake) or dark matter (it is kind of magic). Can those things be defined as pseudoscience.

    2. An hypothesis which cannot be falsified using material, empirical techniques (Popper) is the demarcation between what science can address, and what science cannot address; it is not a demarcation between what is true and what is not true.

      Declaring a statement or hypothesis to be pseudoscience has no bearing on the truth value which the statement might contain; it merely declares that it cannot be falsified by science.

      Contra Scientism, science cannot address all issues and questions of interest or importance to humans, and Philosophical Materialism cannot even prove its own premise: there is no non-material existence.

      Further, as the history of the hypothesis of tectonic plates has shown, charges of pseudoscience are frequently done out of ignorance of facts or out of personal intellectual inertia of those invested in old thinking.

    3. Stan,

      Poppers falsification criteria is rather poor (limited applicability),

      And science addresses a lot of issues that are not subject to this criteria, such as (just to mention a few examples):

      big-bang hypothesis
      anthropogenic global warming
      dark matter

      these hypothesis are not testable, however their value is (tentatively) assessed by indirect confirmation (through consistency with other observations).

      One terrible thing though is that (respectful) scientists and philosophers (incapable of real critical thinking) hold to these hypothesis as undisputable trues (as 2+2=4), on basis only of ideological and tribal consistencies, engage on absurd pseudo-science wars (apparently leaning very little from the pseudo-science wars of the XX century).

  6. Lots of speculation. The main point when you have these states that no longer exist - or cannot be securely observed or replicated (the big bang as well) is not to get too carried away. It's great to be novel and so on, but rather than go off into the strange, we can begin by ackowledging what we do not know about the fundamentals - of chemistry for example. We have a Periodic Table, and some knowledge of capacities of atoms to compound, but far from complete. I'd try to extend from the fundamentals that are already known in chemistry by painstaking work (and likewise in physics) rather than going off planet in biology (or 'something from nothing' at the Big Bang)- too easy.

  7. Alex,

    > I think in this case, seen in isolation, it is the last of the three. It becomes pseudoscience when they have been shown that they are wrong and start with confirmation bias and the moving of goalposts. <

    I would agree, which is why I think this paper is an interesting borderline case. We’ll see what happens.

    btw, I also agree with your analysis of the ID case (though, as you might predict, I would say that it is limited to non-supernatural ID. But we’ve had that discussion before...).


    > This is what defines pseudoscience for me: Any "theory" that introduces the nonmaterial. <

    That seems far too restrictive. Insisting on the reality of cold fusion, for instance, is nowadays considered to be pseudoscientific, but those people aren’t invoking anything immaterial.

    1. I would call cold fusion a junked science, or a disregarded science, but not a true pseudoscience. ID is a real pseudoscience. As ID is formulated, it could never be science at all.

    2. Philip,

      I disagree, the consensus of my co-authors in the forthcoming book is that something qualifies as pseudoscience if it pretends to be scientific even after it has shown not to be the case. Which means that something can begin as science and slide into pseudoscience. And cold fusion is the prototypical case for this class.

  8. I am attracted to Philip's narrow definition of pseudoscience (Rupert Sheldrake comes to mind), but surely there is nothing in particular that pseudoscience is. It is just a term that has been used in various ways over the years. Some definitions may fit customary usage or serve certain purposes better than others, that's all.

  9. (though, as you might predict, I would say that it is limited to non-supernatural ID. But we’ve had that discussion before...)

    Quite so. Unfortunately, I have yet to come across a meaningful and non-question-begging definition of the term supernatural, so "supernatural ID" is currently an empty set to me.

  10. Some years ago I had the idea (as a spoof) to posit the existence of natural entities like "intellitrons" and "intelligence fields" which would do what the ID people say is missing from cosmology and evolutionary theory. I'm surprised they don't approach ID that way, however unsuccessful it might be. But their real interest is to put their nonmaterial God into the mix.

  11. I'm wondering if this series of posts & podcast on science & philosophy isn't really about promoting demarcations when they might not be needed. I reckon its Science to confirm facts, and Philosophy as elimination of facts from a rational explanation of something (or reordering them to get a rational explanation). They intersect in making theories, the rational aspect tending to be Philosophical. and the empirical aspect tending to be Scientific.

    And yes, I would say everything is or requires empirical & rational aspects, so making toast is both scientific & philosophical, without being science or philosophy, as it doesn't (quite) reach their demarcated standards. Where is the line of demarcation between everyday life and the overlapping (but demarcated) areas of science & philosophy? If you want to make the study of science or philosophy something special, then you set it high - if you want plain language and concepts and to hold specialists to that level, you set the line low. I reckon low is the only way to go, and jargon can is the first thing for the trashcan.

  12. 'Supernatural' is, as Alex suggests, a problematic concept, but it (and words like 'spiritual' and 'magical') do have meaning. Generally, I would say, they designate a view of things which rejects the standard scientific view of the world as inadequate, and posits entities or forces which are beyond the reach of anything like current science. (I also think that some people who otherwise reject the 'spiritual' are committed to a belief in some sort of objective moral realm (which, in my opinion, is clearly beyond science).)

    My default position is a rigorously scientific view of the world, but I think we have to recognize that there is no knockdown argument against other views.

    On the various distinctions, the good science/bad science distinction is very much a science-internal question, whereas you could see the science/non-science distinction as being both scientific and philosophical. Bad science, if it is very bad, could be seen as pseudoscience (i.e. not science but pretending to be science). As Massimo points out, bad science can morph into pseudoscience.

    I think it is worth noting, however, that work attracting the designation pseudoscience has historically very often incorporated non-physicalist assumptions.

  13. For materialists, these are synonyms of 'nonmaterial': nonnatural, nonphysical, supernatural, magical, spiritual.

  14. Until science resolves their own uncertainty of measure problem, their results will be nothing but probable or pseudonatural (false in nature) and the furthest from philosophy, the discipline of absolute truth.


  15. Exellenct article, Massimo.

    It seems to me that the problem is that the paper isn't clear about its intentions; whether this is intended to put forward a hypothesis, just pure speculation, or something else, as evidenced by your statement that they skirt very close to pseudoscience. If is was clear, then this probably wouldn't be as much of a problem, or a problem at all. Certainly, PZ wouldn't be so scathing about it.

    For me, the problem alarm really goes off at "biosemiotics." As someone with an interest in semiology, it seems to me that whenever it is brought in, the whole conversation breaks down and people start talking at cross purposes.

    Also, although this is a nitpick, English isn't a Romance language; it's a Germanic language.


  16. Massimo Pigliucci: “Of course the fact that it hasn’t been published, yet, in a peer reviewed journal is an issue; but it’s not like there is no garbage being published by legitimate scientific journals anyway.”

    Many of the ideas in this paper by Sharov and Gordon have been presented before in a paper entitled “Genome increase as a clock for the origin and evolution of life” published by Sharov in Biology Direct, 2006. The paper was peer reviewed by some of the leading experts in the origin and evolution of life: Eugene Koonin, Chris Adami and Arcady Mushegian. The paper as well as the peer reviews are available for free at: www.biomedcentral.com/content/pdf/1745-6150-1-17.pdf

  17. Poor understanding of statistics is also a sure sign of pseudoscience. Even if it were true (and I don't believe it) that “Linear regression of genetic complexity (on a log scale) extrapolated back to just one base pair suggests the time of the origin of life = 9.7 ± 2.5 billion years ago.”, this would still not imply that life originated outside Earth.

    9.7 ± 2.5 Gyears ago is within 2.064 sigmas from 4.54 Gyears. A less than 3-sigma effect means absolutely nothing to anybody with any experience with experiments in fundamental science. Particle experimentalist wait for a 5-sigma effect before claiming to have discovered anything.

    Incidentally, CDMS-II (using silicon detectors,) has 3-sigma evidence for a dark-matter particle with a mass of 8.6 GeV and a nucleon cross section of 1.9E-41 cm2. Nobody is making a big deal about it. I personally believe this is it, meaning that 5-sigma for such a particle is only a few years away.

  18. Massimo Pigliucci may prefer to believe that life spectacularly developed in a very narrow "window of opportunity" between 4.5 billion and 3.8 billion years ago, but I seriously doubt it. As I understand it, the Earth's rocks would have been incandescent for much of that time.

    The "Moore's law" hypothesis is worthy of consideration.


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