The example of deaf people communicating using sign language indicates that we could have been Teletubbies. Chimps can sign effortlessly, while for verbal language one needs to evolve specialized vocal apparatus. No such preadaptation would be required for a gesture-call system. We could have been Teletubbies 1 Mya rather than becoming humans 150 kya.
Gestures, of course, are primitive in comparison to the ability of cephalopods to be live TV screens. The cruel fate that covered mammals with hair robbed us of the chromatophores that would make such displays possible, but that’s a zigzag of evolution. We could’ve been the spitting image of Teletubbies.
Signing, of course, has obvious disadvantages. It takes longer, although on average sentences are completed in the same time, as signing has higher information density (our verbal language is notorious for its inefficiency and vagueness).
But there are advantages, too. We speak against a noisy backdrop, while signing is visually unimpeded. Making a hand gesture slower takes problems of incomprehension; speaking slower rarely does. Perhaps talking in the dark is easier than, say, tapping in Morse code, but it is bed time anyway. Another "explanation" one reads is that human hands were occupied by stone tools, so signing was difficult. Mine are not occupied, and I find this rationale ridiculous.
But there is an entirely different way of thinking about the same problem.
One thing that is not so easy to do if you are a Teletubby is to fabricate imaginative, elaborate lies, to fib. Observe that our speech pursues no goal of reliable communication. When fidelity is important, you can always recognize such situations by dedicated effort that goes into achieving reliability (see Part 1). There are solutions for high high and low processing power; we use neither. Our communication is deliberately confusing. Language is a tool to obfuscate, deceive, and block understanding. The more is left to imagination, the better.
Of many theories of origin of speech the only one that makes sense to me is the theory that language is part of the ritual, the general symbolic culture. The reason we are not Teletubbies is that Darwinian evolution has no means of making Teletubbies to trust each other, because for that they need to be willing to believe a lie, if only passingly. To use speech they need to develop faith. This faith cannot be trusting into each other (that would never work, as explained below). They need to believe and trust their own imaginations. There is no other path to a rational being.
To understand this, one needs to think through the evolutionary consequences of deception in signaling. As this argument has been presented quite well by the others, below is a long excerpt from Knight’s chapter in this book
If you can, read the whole thing, as it is worth it.
...Politics and power relations are inevitably involved in communication. Animal communication is the means by which one individual, the actor, exploits the muscle power of another, the reactor. Where animals have conflicting interests, they will seek to exploit and deceive rather than share good information, prompting receivers to develop corresponding ‘sales resistance’. As conflict intensifies, signals become restricted to displays of fighting or other competitive ability. Such signals are uninformative except in one narrow respect: they reveal the signaller’s ability to meet the costs of the display. The more discernibly costly the signal, the more impressive it is. As receivers incur fitness penalties for being too impressionable, all but the most costly, elaborate, repetitive and ‘ritual’-like signals are simply ignored. The dynamic culminates in extravagant advertisements such as peacock displays.
...Where interests converge, however, this dynamic is set into reverse. Signals then evolve to become less repetitive and ‘ritualized’, more cryptic, quiet and efficient. Signals may now take more effort to detect and decode, but if the information is valuable, receivers should be motivated to invest that effort. This allows signallers to offload costs of communication onto receivers — minimizing redundancy, lowering amplitude and narrowing the range of utilized channels (‘conspiratorial whispering’). Social insects communicating within well-defended colonies offer examples of such highly informative ‘whispering’.
...Cost-cutting comes up against constraints. Where whole local populations are concerned, interests rarely converge except in relation to a narrow range of challenges such as external threats. The problem is that conventional signals depend on trust, whereas those animals intelligent enough to use such signals will also be clever enough to exploit that trust competitively. This may help explain why, despite their cognitive capacities, chimpanzees have no natural use for conventional signals.
... Suppose certain unusually intelligent chimps in a wild population develop a repertoire of volitional vocal signals, each with a conventional meaning. Enterprising animals will soon be using these in tactically deceiving each other. Emission costs will be low, making even small gains worthwhile, putting pressure on all to deceive where possible. On that basis, ingroup trust will rapidly be exhausted, to the point where no-one is listening any more; the system will now be useless for any purpose, honest or dishonest. Since potential conflicts of interest exist throughout the animal world, even between close kin, resistance to deception has always selected against conventional signals — with the one puzzling exception of humans.
...Without the establishment among humans of a new kind of honesty as a default — habitual honesty in volitional signalling — speech could not have got off the ground. In the human case, then, precisely the most unreliable kinds of signals — namely, the volitional, intentional ones — must have become adapted for honest use. Somehow, in the course of human evolution, what were once frequency-dependent tactical deceptions must have become increasingly routine while becoming simultaneously harnessed to a reversed social function — the group-wide sharing of good information. Imagine a population in which volitional signals are becoming commonplace, thanks initially to skills in deception. How can a new honest strategy invade the deceptive one and become evolutionarily stable? An immediate problem is that any increase in the proportion of
trusting listeners increases the rewards to a liar, increasing the frequency of lying. Yet until hearers can safely assume honesty, their stance will be indifference to volitional signals. Then, even lying will be a waste of time.
...In other words, there is a threshold of honest use of conventional signals, below which any strategy based on such signalling remains unstable. To achieve stability, the honest strategy has to predominate decisively over deception; yet the evolutionary route to such honesty seems to pass inescapably across a point at which deception is so rampant that trust in volitional signals collapses. How can this conundrum be solved?
...There are those who argue that the main function of speech was and remains lying. Such claims may appear persuasive, yet this view poses as many problems as it solves. Speech is not only a convention-based, radically arbitrary means of communication; it is also (by comparison with primate calls) minimally redundant, low in amplitude and heavily demanding of listeners. Darwinians view these as the tell-tale design-hallmarks of ‘conspiratorial whispering’ — indicating a system designed for communicating good information to trusting listeners at speed. This implies that speech has been co-operative from its inception. In accounting for the necessary honesty, it is tempting to draw on Darwinian reciprocal altruism theory: if you lie to me, I’ll never again listen to you — so be honest. But even accepting this, we need to explain why the dynamic did not lead to volitional, conventional signaling among those apes which appear cognitively capable of reciprocal altruism.
The suggested resolution of the conundrum is collective self-deception.
...Myths, dramatic performances, art and indeed all expressions of human symbolic culture may in this light be understood as ‘collusion in deception’ — collaboration in the maintenance of fictions which have social support. A community will place ultimate confidence only in those fictions which are emblematic of itself. If all collude, then on another level the deceptive signal may constitute a performative, constructing its own truth.
...A symbolic community is always on some level a secret society, its knowledge inseparable from others’ ignorance and hence its own power in relation to them. An ability to handle fictional representations, then, is the essence of human symbolic competence Distinguishing between surface and deeper meanings poses a major cognitive challenge. The power of words is nothing other than the delegated power of the spokesperson, and his speech… is no more than a testimony, and one among others, of the guarantee of delegation which is vested in him.’ The words of some derided ‘nobody’ have no weight. Utterances have force only through collusion with a wider system of ritual or ceremonial.
...Deployed to certify statements as reliable, they reflect communal resistance to deception. In the final analysis, people are on speaking terms only with those who ‘share the same gods’. The magic of words is the collusion of a ritual ingroup. Withdraw the collusion and nothing happens — the speaker’s words are empty sound. Unlike Machiavellian primates, whose creative fictions prompt countermeasures from those around them, human conversationalists routinely encourage that very resort to imaginative story-telling which in primates is socially resisted.
...All this is far removed from primate-style ‘Machiavellian’ politics. Chimpanzees may play, but their playful fictions are not collectively shared. Given such isolation on the imaginative level, intangibles such as ‘promises’ stand no chance of emerging as publicly available fictional representations — no chimp ever swore on oath. Note, moreover, that for a chimp to freely broadcast relevant information would be maladaptive: opponents would simply take advantage and status would be lost. Chimps, not surprisingly, are as concerned to conceal relevant information as to reveal it.
...Machiavellian primate politics prompts mistrustful listeners to resist all signals except those whose veracity can be instantly and directly corroborated. This immediately excludes (a) volitional conventional signals; (b) displaced reference; (c) signals literally false but metaphorically true; (d) signals meaningful not in themselves, but only in combinatorial contexts. Primate-style resistance to deception, in other words, obstructs the emergence of the characteristics of speech not just on certain fronts but on all fronts simultaneously.
The same relates to Teletubbies. It would be their own misguided insistence on veracity that will prevent them from becoming intelligent, being stuck forever in the BBC playground. This is something one cannot fail to observe even today (the comments to this blog included). Knight puts it well:
...Suppose that whenever I opened my mouth to begin speaking, I found myself instantly challenged, my audience demanding on-the-spot corroboration of the very first sounds, refusing to listen further until satisfied. Denied the chance to express one transparent fiction, modify it by another, modify that in turn and so on, I could hardly display any skills I might have for handling such sequences. Faced with refusal to suspend disbelief even momentarily, I could hardly venture to refer to phenomena beyond the current context of here-and-now perceptible reality. How could I express a fantasy, elaborate a narrative or specify with precision a complex thought, if listeners demanded literal corroboration of each signal as I emitted it, refusing to wait until the end before deciding on a response? Finally, it is difficult to see how my utterance could display duality of patterning if listeners demanded literal veracity on the syllable-by-syllable level, obscuring and resisting the possibilities of meaning or patterning on any higher level.
...My freedom to speak presupposes that you, the listener, are trusting enough to offer me, at least initially, the benefit of any doubt, demanding and expecting more information before checking out what I have signalled so far. I need you to be willing to internalize literal fictions, evaluating meanings not instantaneously, item by item, but only as I construct larger patterns on a higher, ‘combinatorial’ level. By primate standards, such collusion with my deceits would appear disastrously maladaptive.
People erroneously believe that their insistence on literal truth distinguishes them in intelligence. The exact opposite is true, in things small as much as in things large. No intelligence would have existed among those not willing to believe imaginations of the others, and the willingness to contemplate fabrications is the true hallmark of human reason. You can instantly recognize a fool in someone endlessly demanding definitions, proofs and corroborations of every word and/or idea uttered by any one but himself. There is no fundamental difference between such a person and a chimp, and this person restages the same pattern of behavior that kept us in the company of apes long after we had everything needed to depart. If you want truth and only truth, go and live in the zoo with other strivers for intellectual honesty. A human can see truth shining in even the most unlikely fabrication and recognize a lie in the middle of what appears to be rock solid truth. This is what makes us human.
Our language is not designed for speaking truth, it has no built-in features for trustworthiness and reliability, and it does not even aim at them. It aims at imagining and reimagining worlds.
Words do best because they constrain human imaginations the least. That is the real reason we are not Teletubbies.
Blessed is the one who spoke and the world came into being.
בָּרוּךְ שֶׁאָמַר וְהָיָה הָעולָם.