Humanity isn't, it becomes

By Razib Khan | September 23, 2012 7:55 pm

John Hawks prompts to reemphasize an aspect of my thinking which has undergone a revolution over the past 10 years. I pointed to it in my post on the Khoe-San. In short, the common anatomically modern human ancestors of Khoe-San and non-Khoe-San may not have been people. Rather, people may have evolved over the past 100-200,000 years ago. Of course the term “people” is not quite as scientific as you might like. In philosophy and law you have debates about “personhood”. Granting the utility of these debates I am basically saying that the common ancestor of Khoe-San and non-Khoe-San may not have been persons, as well understand them. Though, as a person myself, I do think they were persons. At this point I am willing to push the class “person” rather far back in time.

As I suggested earlier there is an implicit assumption that personhood is a shared derived trait of our species. Or at least it is a consensus today that all extant members of H. sapiens are persons. Since Khoe-San are persons, the common ancestor of Khoe-San and non-Khoe-San must also be persons if personhood is a shared derived trait. But, we also know that there are many aspects of realized personhood on a sociological or cultural scale which seem to diminish the further back in time you go. For example, the Oldowan lithic technology persisted for ~1 million years. A common modern conception of persons is that persons in the aggregate are simply never so static. Persons have culture, and culture is protean. Therefore, one might infer from the nature of Oldowan technological torpor that the producers of that technology were not persons.

But there’s a large gap between the decline of the Oldowan and the rise of anatomically modern humans. Where to draw the line? Let’s take a step back about a decade. Here’s an extract from Richard Klein’s excellent Dawn of Human Culture:

Our third and final observation is that the relationship between anatomical and behavioral change shifted abruptly about 50,000 years ago. Before this time, anatomy and behavior appear to have evolved more or less in tandem, very slowly, but after this time anatomy remained relatively stable while behavioral (cultural) change accelerated rapidly. What could explain this better than a neural change that promoted the extraordinary modern human ability to innovate? This is not to say that Neanderthals and their non-modern contemporaries possessed ape-like brains or that they were as biologically and behaviorally primitive as yet earlier humans. It is only to suggest that an acknowledged genetic link between anatomy and behavior in yet earlier people persisted until the emergence of fully modern ones, and that that postulated genetic change 50,000 years ago fostered the uniquely modern ability to adapt to a remarkable range of natural and social circumstances with little or no physiological change.

Arguably, the last key neural change promoted the modern capacity for rapidly spoken phonemic language, or for what anthropologists Duane Quiatt and Richard Milo have called “a fully vocal language, phenmiized, syntactical, and infinitely open and productive.”

The non-moderns were not ape-like, but they were clearly not human-like, if they lacked language as what we understand language to be. Today this view is likely in the minority position, but why? I think the possibility of admixture between these distinct human lineages suggests that the gap between “them” and “us” was not quite as large Klein postulates above. And even then there is a major problem with Klein’s thesis: there was mitochondrial and archaeological evidence even then that the divergence of the Khoe-San and non-Africans far pre-dated the 50,000 year time period alluded to above. Since then the evidence has become even stronger that the divergence of the Khoe-San from other humans, and likely Africans from non-Africans, pre-dates the emergence of “behavioral modernity.”

An implicit assumption that personhood is a shared derived trait from a common human ancestor to me speaks to the same needs and urges which posit a specific ensoulment or creation of humanity from clay. Our minds are not very good at continuities, so we must create distinctive breaks. One moment an animal, and another moment a man! The occasional scientist who speculates that there may be a set of genes which define humanity I think falls into the trap of assuming discontinuity where there is none. There may be no genetic variant necessary or sufficient to being a human. Let me finish by quoting John Hawks, who inspired me to be a bit more explicit in my own line of thinking:

Personally, I think that “cognitive modernity” is a red herring. Today’s people learn some kinds of technical and symbolic complexity that were never present in ancient peoples. Some people living today in Western cultures, despite all our educational efforts, fail to attain levels of technical knowledge that are regular outcomes for the majority of people in the same environment. Human performance varies continuously.

I assert that it is unreasonable to suppose that Neandertals had a “stupid gene”. If so, it should be just as unreasonable to suppose that a “smart gene” could explain the evolution of human cognition during the last 100,000 years. These unrealistic assumptions are widespread, and impede our understanding just as thoroughly as assumptions about the nature of biological species impeded our understanding of Neandertal ancestry of living human populations. Some archaeologists have concluded that Neandertal cognition is an either/or proposition. Some look at Neandertals, find a lack of evidence that they behave identically to later people, and conclude that the Neandertals were therefore unquestionably cognitive inferiors. Others look at Neandertals, find some signs of modern-like behaviors, and conclude that Neandertals were therefore unquestionably our cognitive equals.

Cognition in modern humans varies continuously across many axes of variation. No two humans are cognitively identical in outcomes. Nor can we appeal to “cognitive capacity”, a meaningless abstraction unless we are discussing a particular structured learning environment in which the outcomes are potentially measurable. Will we someday raise a Neandertal in a human society to see whether and how they attain the skills and abilities we consider essential?

CATEGORIZED UNDER: Anthroplogy, Human Evolution

Comments (53)

  1. Dwight E. Howell

    I think people are missing the obvious. Culture is what is changing and you need a rather lager mass of people who are doing well enough to have at least some free time, a method of storing data if only in the minds of a few long lived members of the group, and hopefully communication with other groups in order to bring about what is now considered a human rate of change.

    A population of small scattered groups composed of short lived individuals who spend all their time trying to stay alive and rarely make contact with others is going to be doing well to hold on to what ever culture they may already have and isn’t particularly like to transmit any new ideas to that occur to them to others.

    We can only accomplish what we do by building on the accomplishments of those who came before but first you have to know what those accomplishments where or you end up re-inventing the wheel rather than the oxcart.

  2. Tim

    I’d move that red block to the branching point of the Denisovans, Neanderthals and Moderns

  3. #2, who do you think you are, yahweh? 🙂

  4. RedZenGenoist

    Is a clinically brain dead homo sapiens a “person”?

  5. #4, follow the ‘personhood’ link. there’s been a lot of ink spilled on that issue.

    (and no, i don’t think they are personally, but i don’t believe in a ‘soul’)

  6. It’s interesting how everyone attains their own, personal viewpoints for what is and isn’t human, either when speaking of the population clusters/races as possible sub-species, or Homo sapiens sapiens VS Homo sapiens idaltu, or Homo sapiens VS Homo neanderthalensis (some categorize them as Homo sapiens neanderthalensis, which is fine with me), or what stage does an egg’s and sperm’s combination attain human status.

    I know I’m re-iterating tired points, but it’s exciting that as we gather more genetic samples and build upon future information, we can uncover such truths. It’s an exciting obsession for all of us! 🙂 Part of me doubts we’ll ever achieve universally agreed taxonomies.

  7. RedZenGenoist

    #5: I expect that, in the near future, there will be some kind of legal definition of personhood which means “mind”. And that some, severely compromised humans will be unable to pass it, while a few animals (and an increasing number of AI) will.

    Once this precedent is established, the next step may be to abandon the binary definition of person/not-person, and to add additional levels above “person”, based on additional criteria.

  8. #7, yes, i anticipate this sort of difference. i think AI, if they ever exist, will be persons.

  9. Andrew Lancaster

    Hmm. Over the years on blogs like this we’ve seen the difficulty of trying to turn the word race into a proper phylogenetic word. I think the case is still out on it, but the cause seems good.

    However, trying to turn the word “personhood” into one seems to me to be too much a stretch? I’d agree with the comments already posted now that personhood is not normally even understood as physical. If we ever learn to upload a human to a machine, I think a lot of people would think that this is still a person.

    Should get lots of comments though! 🙂

  10. Karl Zimmerman

    Technically speaking, behavioral modernity could still have been a recent adaptation even with the LCA of all modern humans being behaviorally modern, if you:

    1. Presume behavioral modernity was a “software” upgrade which spread across disparate populations into brains which were “primed” for it for a long period prior.

    2. Presume that behavioral modernity was advantageous enough that it’s a trait which evolved more than once through convergent evolution. After all, numerous human technologies (agriculture, metalworking, animal husbandry, written language, etc) clearly developed more than once, and even “killer apps” like agriculture didn’t always cause earlier peoples to be completely replaced.

    Only the form of the “Great Leap Forward” which postulates a particular mutation allowed for behavioral modernity is really debunked now.

    More generally, I first ran into the problem of people still assuming the “specialness of humans” many years back when I was in a political theory class. The class was on human nature, and the professor liked biology a lot more than most professors in the social sciences (we had to read some Matt Ridley for the class for example). Regardless, I brought up the point in class that if you believed in human evolution, you must admit that there was such a thing as a “partially conscious” being, as to think that a fully-conscious human was suddenly born from unconscious parents at some point is magical thinking. The majority of the class had a very difficult time with this concept for some strange reason, despite everyone in the class having a highly secular outlook but one student (I was in the UK, not the U.S., that year).

  11. Simon

    @10 Karl –

    If the recent-mutation-based hypothesis is debunked, then I’m not sure how one would describe the status of the ‘software upgrade for the brain’ hypothesis. Is there something worse than ‘bunk’ that can be removed?

    As to students in a politics class unable to think in shades of grey…

  12. Karl Zimmerman

    Simon (11) –

    One hypothesis I have heard is based upon how humans not exposed to advanced language in childhood don’t ever develop a capacity for advanced thought. Essentially, that humans were intelligent, but all but pre-linguistic, for some period of time, speaking a simple pidgin. However, at some point, humans from two quite different linguistic groups were thrust together. Their offspring turned the pidgins of the originating tribal groups into a fully-formed creole, which became the first complex language.

    This hypothesis had one advantage – it can “jump” ethnic groups, given if a small post-linguistic group takes over or settles into a pre-linguistic community it can result in all children, even those who aren’t direct offspring, becoming advanced thinkers.

    That said, there are some issues with it. For example, social mixing should have been fairly routine in the early history of AMH, thus this should have been presumed to have happened numerous times. In addition, it suffers from the “hopeful monster” problem – how could humans have the capacity for advanced symbolic language for many generations without using it? The latter isn’t impossible, as certain advanced skills to have plausible antecedents (for example, math skills may have been needed to understand how to throw an object on a subconscious level), but I don’t think there’s been a plausible explanation of what our linguistic skills would have been used for in the absence of language.

  13. The original U.S. Constitution famously considered slaves to be 3/5 of a person (Article 1, Section 2, Paragraph 3) for the purposes of calculating the number of representatives. It goes without saying that this is the most abhorrent part of that document. But the idea of “fractional personhood” might indeed be relevant when discussing extinct stem-humans. Was Homo ergaster 3/5 of a person?

  14. Karl Zimmerman

    Personally, I think personhood ought to mean the ability to actively state one’s own desires – most ideally the ability to testify in court. I think it’s dangerous to allow beings with no ability to actually state what they want to have “rights” because they then can easily become proxies for people who “interpret” what said beings desire.

    That does not imply, however, that there should be no laws dealing with treatment of non-persons. I’d argue in a legal sense infants shouldn’t be considered persons with any agency independent of their parents, but that doesn’t mean that I think it’s okay for parents to kill them if they so desire it.

  15. Could the Great Leap Forward mutation still have occurred 50ky ago and then swept through the other populations through the limited genetic contact that (I assume) still existed? There’s a difference between being mostly isolated genetically and completely isolated.

  16. Simon

    @Karl (12) –

    I realise there’s more than a hint of devils advocate here, but the shear voracity with which most young humans learn language, compared with the slow painful progress in other – obviously secondary – skills makes that particular idea seem improbable.

  17. That does not imply, however, that there should be no laws dealing with treatment of non-persons.

    i don’t think chimps should be treated like mice should be treated like cockroaches. but i’m partly a phylogenetic bigot. should i feel guilty for having eaten squid? pig? interesting to reflect upon. when artificial meat, whether lab tissue culture or ‘fake meat’ gets good enough i will probably eat that in preference.

  18. pconroy

    I would love to see being human defined in terms of thinking – as then we would find that most people aren’t human 😉

  19. pconroy

    In all seriousness, I think we were human from Homo Ergaster forward… all extant and ancient Homos are but his children and grandchildren.

  20. I’d like to continue the language issue before it drops off. As pointed out in 12, barring severe retardation or a sensually-deprived upbringing (e.g., “Nell”), every human can and will develop language, even if it’s sign. It seems like the capacity for linguistic production would be part of what defines a person?

    And yet, if Chomsky is even sort of right, then the advent of human language was indeed a “moment of creation”, as it were, a mutation that arose at a very specific time and place. While I don’t subscribe to half of what Chomsky says, I think it’s hard to deny that the structure of language does depend on only a few simple operations that could be controlled by electric pulses in the brain: YES, NO, IF/THEN, et cetera . . .

    This syntactic/neural interface, and the incredible capacity for abstraction that it allows, has no analogue in any other species; trying to point out similarities between human and non-human communication has the effect of making the differences seem even larger. In 12, KZ hints at the problem, but I think it’s even more difficult than he allows. In most linguistic frameworks, a “pidgin” arises only in relation to a fully formed language. In other words, it’s difficult to assume that linguistic complexity is an evolving variable because most evidence points toward the fact that language is always already complete, or it wouldn’t be language (i.e., it wouldn’t be phonemic, morphemic, syntactic, and semantic).

    Again, I’m no Chomsky disciple, so this is perhaps a devil’s advocate position: but if I’m going to entirely abandon the possibility of a “cutoff” for human/non-human, then I think I’ll need some evidence that language is not an either/or capability, i.e., that other species or archaic hominids had productive phonemes, morphemes, and syntax.

    Now, there has been some work done on “language complexity as an evolving variable.” However, I’m not sure that the bleeding-heart liberals amongst us would be quite so quick to go down that road. After all, if language does indeed evolve, then perhaps those terrible colonials were right that not every language has evolved quite up to par with every other . . .

  21. And yet, if Chomsky is even sort of right,

    the language issue is separate from chomsky’s rightness about evolution. but chomsky doesn’t know much about evolution.

  22. Simon

    @Brian (15) –

    Your actual question will have to be answered by somebody with a clue, but even if we assume that such a sweep could have happened, my question would be “what evidence is there that requires this explanation?”

    The more archaeological work done in Africa, the more counter examples to modern uniqueness are found, and the less special modern behaviour seems, so the less need there is for any special event giving us an upper paleolithic revolution.

  23. Simon

    @Seth (20) –

    “And yet, if Chomsky is even sort of right, then the advent of human language was indeed a “moment of creation”, as it were, a mutation that arose at a very specific time and place.”

    This seems really most unlikely. A single point mutation that produced the human larynx and the ability to mentally construct sentences and the ability to understand them… nah.

  24. D. N. Irving, Ph.D.

    Although a thorny issue, I see indefensible influences of “process” philosophy here. Can something come from nothing? Definitions of “person” have recently been proclaimed to advance various “isms” — e.g., transhumanism, futurism, postnaturalism, posthumanism, artificial intelligence and robotic “isms”, even “bioethics-isms” (is there such a word?!), etc. But all such definitions of “person” seem to be reductive and simplistic, making various “splits” or fragmentations of what is a whole intact human being already possessing both active and potential properties and functions. And all such definitions have real-life consequences that should be seriously considered — and admitted. If “person” is defined only in terms of Singer’s “rational attributes” (knowing, willing, relating to the world around one, choosing, etc.), then even the following adult human beings are not “persons”: mentally ill, the mentally retarded, the comatose, demented elderly, drug addicts, alcoholics, maybe even teenagers — and all of us when we sleep, are under anesthetics during surgeries, etc. Therefore all such human beings would not deserve the rights and protections afforded real “persons” (and consider those consequences). If “person” is defined only in terms of Singer’s “sentience” (ability to feel pain/pleasure), then even adult paraplegics, those with neuropathy, and most of those identified above are also not “persons”. If “person” is defined using erroneous or false scientific, philosophical or paleontological “facts”, then such definitions are baseless, but just as potentially damaging.

    D. N. Irving, Ph.D.
    (science and philosophy)

  25. #24, you read like a deconstructionist 😉 shorter: i’m catholic.

  26. am i wrong in assuming our speech is based on more ancient brain modules (from birds)?
    i thought that’s why we get songs stuck in our head so easily.

  27. Random Rambler

    “Should i feel guilty for having eaten squid? pig?’

    I think the needless harvesting of sentient beings for raw materials is morally problematic, but I haven’t given it as much thought as I’d like. I do recognize a contradiction in how I approach the treatment of my dog, and dogs in general, versus pigs. Anecdotally, it seems to me that the widespread moral indifference toward meat-eating, and the meat industry, requires a degree of self-deception–particularly regarding an ontological distinction between humans and animals.

    I just came across this opinion piece on NS, which may be interesting.

  28. Random Rambler

    #24: I don’t quite understand what you’re saying, but I am interested. Could you quote something specific in the above conversation that you are intending to speak to? I didn’t think that a definitive, all-encompassing definition of ‘person’ was really anyone’s point. But perhaps I lack a sufficient understanding of the issues. Thanks.

  29. Karl Zimmerman

    15 –

    The problem I see it is if behavioral modernity was a single-point mutation, and advantageous enough to be strongly selected for, then selection would proceed so quickly that a whole lot of attached genes would also come along for the ride – meaning the resulting human race would only have a comparably small substrate of pre-mutation admixture.

    16 –

    We don’t just have feral children here to look at. A fair amount of deaf children who aren’t exposed to sign language as children essentially remain pre-linguistic (understanding sign no better than a chimp). There’s a startling story I read recently (I’ll try and find the book when I get home) of a deaf man who became linguistic fairly late in life (in his 20s). When he “figured out” language he had a sudden moment of shock, realizing “everything had a name.” He remains unable to describe anything about his own thought process prior to learning how to use language.

    23 –

    Language could predate the dropped larynx if sign language predated spoken language. Similarly, humans might have dropped their larynx for other reasons (related to singing, perhaps), and later had it co-opted for language. Thus I think you could link it back to a single “mental mutation” – except if only one human had the mutation, they’d have no one to talk to. Heh.

  30. Random Rambler

    @KZ, who wrote, “humans might have dropped their larynx for other reasons (related to singing, perhaps), and later had it co-opted for language.”

    What about those who think (e.g., J. Diamond, “The Third Chimpanzee”) that vervet monkey alarm calls constitute an animal precedent to language? I mean, could comparable “animal” behavior among our hominini ancestors have influenced selection for the dropped larynx? Although, I guess high-frequency alarm calls are what is selected for in vervets because they are less easily localized by predators. (I’m just assuming that dropped larynx translates to generally lower pitch.) And my understanding is that chimpanzee larynges are only slightly higher than humans, which makes me wonder if a relatively small change in position could have had very significant selectable effects.

    (Forgive me, these topics are far outside my area of expertise, but I am interested.)

  31. AllenM

    Ye gawds, nice ripost R.K. re 24.

    Informed consent. What an interesting concept to ignore- I trotted my brother in law into one of the largest catholic hospitals on Sunday morning through the ER- Kidney stones causing severe blockage. I note they discussed financial responsibility after they provided the morphine in the IV- so was his provision and signature on the financial responsibility that of full informed consent granted by a person, or of an animal that would sign anything to stop the pain? I bet a good lawyer could successfully argue the latter.

    Fragmenting of person as evil is a most likely response to degrees of grey that the Catholics have resisted ever since the conflict. Or just look at the Lucretian atoms leading to Epicurism versus the Jesuit Position.

    Irving’s philosophy reeks of “trust us” because “we know better”, and we have to defend our soul based philosophy in a scientific, rational way, because birth control is evil, and stem cell research resembles birth control- and there might be viable embryos destroyed along the way that are “persons”.

    Taking her argument to absurdem: Any stem cells harvested from me, and not used in an approved bioethical fashion, should be bioengineered into viable fetuses and implanted into replicators and then born.

    While this statement sounds risible on it’s face, after reading this quote from her long screed “I have attempted to briefly present the well-established objective scientific facts which establish beyond any shadow of a doubt that the immediate products of both sexual and a-sexual human reproduction are innocent living human beings.”

    My stem cells demand parturition!!!

    I guess one needs to understand where anyone starts from to see where they are going with most of these arguments that end up in “bioethics”.

  32. pconroy

    As I’ve sated previously, IMO, language surely developed in hunters as a way to mimic animal calls – be they mating calls, or calls of distress – which were geared towards luring an animal towards hunters, allowing it to be ambushed more easily.

    As a kid I was able to imitate the distress call of a calf, and could get cows to come running towards me…

  33. Random Rambler

    Dr. Irving: I think the Catholic philosophical tradition is fascinating and I am quite interested in such a perspective. However, I am unclear on how your remarks actually pertain to the above discussion (no doubt my fault; forgive me).
    Perhaps if extinct taxa such as Neandertal or H. erectus were “resurrected” – Jurassic Park style -there would be a pertinent ethical and juridical debate to be had. As a general philosophical/metaphysical issue, the idea of a complete definition of “person” strikes me as more useless than an absolute definition of “species,” or “life.” Where fuzziness or context-dependency abound, best to be flexible, I think. What do you think?

    @32 pconroy: Interesting. Do you have any book or paper recommendations? (And while I’m merely an interested layman, I am willing to work through difficult texts.)

  34. pconroy

    @33 RR,

    No book recommendations, as I haven’t written any yet 😉

    My opinions are based on my powers of observation and applied rationality…

  35. Syon

    Mike Keesey:”The original U.S. Constitution famously considered slaves to be 3/5 of a person (Article 1, Section 2, Paragraph 3) for the purposes of calculating the number of representatives. It goes without saying that this is the most abhorrent part of that document. But the idea of “fractional personhood” might indeed be relevant when discussing extinct stem-humans. Was Homo ergaster 3/5 of a person?”

    Of course, if the slave-owners had had their way, slaves would have counted as a full-person for calculating representation in Congress; the three fifths rule was actually an anti-slavery measure.

  36. Random Rambler

    @34: I see. Well, I am interested in hypotheses regarding to origins of bigger brains, abstract thought, language, and the like. I’m definitely more interested in learning than in sharing my own thoughts at this point.

  37. #35 – Thank you. Few things more annoying than outrage over the evil 3/5 Rule.

  38. BDoyle

    Richard Klein almost gets it right, I think. Cultural evolution and biological evolution look like they become de-linked about 50,000 years ago. But….there is no plausible genetic change that could have occurred then to cause this because of behaviorally modern humans being rooted long before this.

    So, I think we have to look for non-biological causes for this. There are some astonishingly old finds of modern-looking tools at sporadic locations in Africa, but the technology seems to pop up and then disappear, being reinvented elsewhere. It may be that a critical mass of people lived somewhere, sometime, that was persistent enough to spread.

  39. Seth

    This seems really most unlikely. A single point mutation that produced the human larynx and the ability to mentally construct sentences and the ability to understand them… nah.

    Ha. Noamy would of course agree about the human larynx but disagree about the ability to mentally construct sentences.

    Like I said, I’m no Chomskyite, and I’m bringing this up as a devil’s advocate: as far as I can see, though, if you take away any level of the lexicogrammar, you simply don’t have human language. So how does language “come into being” from those smaller parts?

    An obvious point: the vocal tract is much more than a larynx. The evolution of language would need to involve, not just a dropped larynx, but the ability to manipulate the vocal tract to produce discrete phonetic sounds; and the ability to put those sounds into discrete phonemes; and the ability to pattern those phonemes in meaningful ways . . . But what is the adaptive value of any of these abilities, on their own, divorced from a full linguistic ability? Minus a ‘language gene’, what would be the adaptive pressure for, say, morphemic production?

    Again, I’m not asking because I disagree with the argument in the original post; I’m asking because these are, in a simplified form, the kind of questions the true-believing Chomskyites in my department would ask . . .

  40. Cecil New

    I was going to comment on the darker side of the idea of animals or AI beings having personhood. #24 has covered the same thoughts. But just to expand a bit… if you allow personhood possiblilities (you choose the metrics) for animal and AI beings, then the corrallary is that humans that do not yet share or no longer share those metrics may be treated as non-persons. This is pretty much the Singer ethic, leading to acceptance of abortion, infanticide, and euthanasia.

    And once these ideas have cultural acceptance, they can be horribly abused during times of social upheaval to apply those with a different skin color or who belong to a different tribe.

    I think I’ll side with the philosophers on this one!

  41. Cecil New

    I don’t think anyone mentioned that the notion of fractional souls is covered by Douglas Hofstadter in his book “I am a Strange Loop”. He avoids a strict materialist perspective by using the dictum that the sum is greater than the parts. I think his approach has a lot of insight.

  42. And once these ideas have cultural acceptance, they can be horribly abused during times of social upheaval to apply those with a different skin color or who belong to a different tribe.

    this is bizarre. you think people need some deep philosophical reason to engage in the things that you fear? people have been killing people of other tribes even when they share the same religion.

    I think I’ll side with the philosophers on this one!

    do you mean this more than rhetorically? if so, that’s awful stupid sounding to me. singer is a philosopher, and in fact i i suspect that the average non-christian philosopher might be more open to various things which you might find disturbing.

  43. He avoids a strict materialist perspective by using the dictum that the sum is greater than the parts. I think his approach has a lot of insight.

    since you’re a fan of philosophy, shouldn’t you be saying he avoids a strict reductionist perspective? clarify please.

  44. T

    I’m seeing a lot of pro-modern human bias. We know that modern humans were more fit, but that just means that they had more surviving offspring. There are many possible reasons why modern humans were more fit, and they aren’t all noble sounding like “our ancestors were much smarter and could talk”. Modern humans had smaller skulls than some of their rivals, and modern human skulls have been shrinking over time.

    quote: “A smaller brain is the signature of selection against aggression,”

    I think that “the event” was that humans became domesticated (by each other). People got better at following commands of the leaders, and spent less time fighting for leadership. Less in-group fighting = more out-group conquering. So rather than something glorious like discovering the secret of language, I think that it was something like becoming the first domesticated humanoid.

  45. Anthony

    Seth @ 39 – pconroy @32 seems to answer your question in advance. Vocal mimicry has evolved a number of times in the animal kingdom; surely parrots didn’t develop it in order to be fed by humans who thought it amusing. Once the range of sounds which can be mimicked is large enough, phonemes can exist. The rest is mental, not laryngeal.

  46. Tim

    ” Razib Khan: #2, who do you think you are, yahweh?”

    No, but I do think it’s likely that the H. heidelbergensis LCA for Moderns, Neanderthals and Denisovans was cognitively advanced enough to warrant the label of person.

    I can’t help but wonder what it would have been like to be that first fully conscious individual. It must have been a bizarre and lonely experience.

  47. #46, perhaps behavioral modernity took so long because the first conscious people kept committing suicide?

  48. Tim

    Dear God, that’s a brutally bleak outlook and a disturbingly plausible one.

  49. chris y

    Of course, if the slave-owners had had their way, slaves would have counted as a full-person for calculating representation in Congress; the three fifths rule was actually an anti-slavery measure.

    Probably not. If slaves had counted as full persons for purposes of representation, they’d have had to count as full persons for tax purposes too.

  50. pconroy

    @46, Tim,

    Well the “first fully conscious individual” – as defined by Jaynes – lived much later than the invention of writing, and in a sense Schizophrenics behave like they are NOT fully conscious. Indeed I would extend the analogy and say that anyone whose life is “guided” by a God like voice offering advice/rebuke in not fully conscious.

    @44, T,

    Don’t believe everything you hear on NPR – I know 2 broadcasters there, who are well meaning, but have imbibed too much left-liberal koolaid and not enough science for them to have opinions worthy of being broadcast, especially in the realm of science.
    As regards skulls becamming smaller and less robust, IMO, after cooking with fire was available, as huge jaws/mandibles and their muscles attached to the head were no longer necessary, and the bones became smaller and less thick, and the shape changed.
    As regards smaller brains; first large brains – think Neanderthal and possibly Denisovan – were, based on a recent paper, a result of hominins living in Northern latitudes, with low light levels and hunting, where more visual cortex for signal processing is required to process images of animals. This is not the case at more tropical locations, where light is good year round. So brains becomming smaller, IMO, could be the result of 2 processes:
    1. Colonization by peoples evolved at lower latitudes – who possessed smaller brains
    2. Evolution of more executive function in the human brain, with a corresponding division of labor between the hemispheres – so you get localized specialization and a better optimization of command and control in the brain – therefore needing less brain volume to accomplish the same tasks.

  51. Naveen

    Science has been a great tool for humanity and major part of it is the use of analytical thinking and the accompanying reductionist approach is for the major part successful but trying to subdivide things and classifying further and further has become an epidemic in people’s way of thinking, we think we humans are all the same some of the time and then we rapidly classify and subdivide, a typical persons thinking might go like this (assuming I am typical on which I am basing my conclusions) ” oh I am only gonna support the efforts of the democrats as they have all the good policies ” “this religions principles seem more right” and then from thinking about the world as a whole we focus on individual countries then states then our favorite town and rally behind our fav football team, then our families and then to the most part whether this is beneficial for me or not for the most part, we should probably start thinking in holistic terms I guess …maybe then we will avoid saying things about this or that what constitutes humanity and humans…and our criterias might be a bit more accommodating

  52. Eurologist


    People think differently about the role of language – in part because of how they perceive their own thinking.

    From when I was a child, I have always been confused by the emphasis on the role of language, since all of my more compelling thoughts seem to develop outside of it, and I often struggle finding language to express them. There are to-me-clear concepts and relations but they may not correspond to immediately obvious words or linguistic ideas/expressions (but perhaps to related ones in other fields – which would explain a lot of internal borrowing in linguistics, like using musical terms for engineering, etc.).

    So, from my (admittedly rather naive) vantage point, complex language evolved to be able to express preexisting complex, personally understood concepts, relations, and processes – not the other way ’round.

    In fact, I like “known concepts,” because to me they are real-existing things/thoughts that other people put the work into to label and describe them so now they have a word. 😉

    Of course, in a highly evolved society, these things tend to back-feed and work hand-in-hand. Expressed differently, to me, language is the cart, preexisting thoughts and ideas are the horse/oxen.

  53. pconroy

    @52 Eurologist,

    Agree that the role of language in the framing of thought is overplayed – but then the people who do this are usually those in the media, who “think verbally” and are poor at other forms of thinking.

    For instance ideas or theories about ancient admixture events and migrations come to me easily, because I dream in maps. I’m a cartophile and much of my thinking is in the visuo-spatial range. I will literally wake up sometimes and find myself looking over a vast map of peoples and places…


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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