Michael Tomasello. A Natural History of Human Thinking. Cambridge, MA: Harvard UP, 2014. Hardcover. 192 pages. $35.00. ISBN: 9780674724778.
Good things come in small packages, and so this is true of Michael Tomasello’s A History of Human Thinking. Of course readers need to understand that along with his very challenging and intriguing argument Tomasello (Co-Director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany) brings many years of expertise and research, so his elegant book simply makes it look easy. By his own admission, Tomasello calls Human Thinking a sequel to his 1999 book, The Cultural Origins of Human Cognition, though our emphasis will be on the later book which charts the evolution of primate cognition and human thinking in terms of cooperation. Tomasello’s cartography of primate cognition and human thinking is persuasive in spite of the limited fossil and artifactual evidence – a masterful reconstruction of how the human mind worked in prehistory from individual needs, to joint efforts, to the collective intentionality of modern human beings. Tomasello’s Natural History of Human Thinking is an important book not only for cognitive, developmental, or evolutionary psychologists but for scholars working in the humanities seeking a deeper understanding of what makes us human. Tomasello lucidly and competently addresses and answers the question of how human beings evolved ape-like mental abilities into highly sophisticated social thinking.
In Human Cognition Tomasello argued that the unique ability of human cognition arises by virtue of a person’s development within a rich and stimulating culture which then becomes internalized and works as an engine of the cognitive mechanisms. In Human Thinking Tomasello takes all of this a step further and argues that the human ability to cooperate, in ways far beyond any such behavior in great apes, is what fostered and currently undergirds our ability to think. In his comparative research between human beings and great apes (chimpanzees, gorillas, orangutans, and bonobos), Tomasello concludes that a crucial difference lies in the human ability to share intentionality for a common goal, completed by elements that include advanced capacities for representation, inference, recursive reasoning, and self-appraisal. Culture, he argues, is not just a vehicle to transmit ideas and practices but is one of the main drivers of bridging different human minds together in cooperative activities, which has its roots in early people dividing labors in hunting and foraging missions. At the bottom line, what we call thinking is an ability for the individual working with other minds to invent cognitive opportunities, strategies, and answers to complex problems of environment and group living.
Preliminarily, Tomasello offers a background in which he discusses his ideas in the tapestry of other thinkers. Hegel (1807) and later Collingwood (1946) say culture is responsible for thinking; Pierce (1931-35) sees specific thinking grounded in “symbolic artifacts” (1); Vygotsky (1978) and Bakhtin see culturally symbolic artifacts as psychologically implanted from a young age and producing an “internal dialogue that is one prototype of human thinking” (1); Mead (1934) sees imaginative perspective taking as responsible for thinking; Piaget (1928) sees language and culture not just in perspective taking but in cooperative reasoning where one aligns oneself to a group; Wittgenstein (1955) finds culture and language in a “preexisting set of shared social practices and judgments” that govern (2). Tomasello sees all of these thinkers as “social infrastructure theorists” who envision language and culture as something that merely varnishes what it means to be human without questioning any comparative cognitive continuity with great apes.
Great apes are capable of understanding causality and intention on a limited, personal scale, and the human capacities for advanced culture are not without deep and distant connections to some of ape behavior. The differences between ape and human behavior are, of course, pronounced. Human infants are cognitively aware and functioning beings, in ways apes are not, before language and culture have set in, proving that there are innate mental modules (2). The major difference between apes and human beings is that we are able to coordinate and collaborate in a truly collective manner and, therefore, construct great physical objects and institutional enterprises, whereas apes tend to look out for themselves even if they are functioning in a group. Nonetheless, higher human cognition, such as recurrent thinking about what others are thinking and our tendency to communicate intentions for another person, are built on evolved intuitions (3).
Human beings, and not animals (though a nod here to Frans de Waal’s 1999 article “Anthropomorphism and Anthropodenial”), can perform objective thinking with representations, argue a point with reasons, engage in social reflection, make inferences, and evaluate mental functions in terms of norms and self-appraisal (4). These capabilities, Tomasello says, are all meshed into “shared intentionality” to accomplish common, coordinated, collective achievements, which is far more advanced than primate joint intentionality geared to individual needs in a competitive but social environment (4-5). Such a major difference (with mutual prehistoric roots) between the great apes and human beings is not accidental, since some of our hominin ancestors (e.g., Neanderthals) also had capabilities like ours. What we now call culture flowered from a long evolutionary history, detailed in Tomasello’s book, spanning “collaborative activity,” to “cooperative communication,” and culminating in “collective intentionality” (5).
Simply because human infants are born with adaptations for cognitive behavior does not imply that collective intentions will occur. Rather, Tomasello asserts, there must be a supportive and nurturing cultural milieu for such “cooperative cognition” to develop (6). Natural selection is responsible for cognition, but cognition in itself is not the product of natural selection: the ultimate processes and outcomes of such cognition are what count in natural selection. But this does not mean, as Tomasello uses as an example, that for all of its advanced understanding of physical and spatial contexts a spider spinning its web acts cognitively. Instead, there must be very little sureness about one’s environment so that, over the course of time assuming the organism survives, natural selection will empower the individual with the ability to imagine what if. Because he has expertly studied apes with various teams of researchers over time, at this point (and hereafter in the book), Tomasello offers examples of chimpanzee behavior. Here, for instance, a chimpanzee sees a tree with ripe bananas, and so internal evaluations and decisions are made about the prospect of getting the food in spite of any real or potential dangers (11).
There is a theory of typing experiences, where an individual stores in memory a schematic action-response which can be called forth in a similar situation, a catalogue of one’s life history in feelings and especially images (12). Some of this schematization can be iconized in a species – the example of the chimpanzee and the bananas. With such schemas available, as if one is looking at a sketch of one’s past, inferential thinking about possible outcomes begins, and the individual (true in chimpanzees, bonobos, and orangutans) essentially diagram a scenario. Such thinking combines evaluating causes, weighing conditions, and predicting results, a cognitive process. Human beings and great apes have much in common, notes Tomasello, from morphology and basic brain construction to emotions, so there is clearly an evolutionary connection, and we can see in certain experiments that apes and human children behave similarly.
At this point, Tomasello takes a closer look at apes in the physical world. In terms of cognition, apes evolved in an environment where there was competitive foraging for food, and so some skills selected for include “spatial navigation,” “feature recognition,” and miscellaneous abilities associated with cause-and-effect and enumeration (15-16). All great apes, compared with other mammals, are skilled with simple tools and can even use one tool to get or make another (16). Chimps, in addition to grasping causality, can infer from effect to cause. For instance, experiments show that shaking food in one of two cups can make a chimpanzee realize that such noise could be something edible, since she was previously shown food beforehand. Likewise, the chimpanzee knew that no sound meant no food and further inferred that the food would be in the second cup (17-19). Since in such an experiment (other tests are outlined) great apes employ causal principles (such as if-then and if-then-not), make inferences, and cognitively assess themselves in the process, they are, Tomasello avers, thinking (20).
In the social world, Tomasello tells us, cognition in primates evolved in competition scenarios – not just for food and other assets but for sexual partners. More specifically, cognitive functions evolved within a defined group so that individuals and their respective relationships could be differentiated, hierarchies could be established, and coalitions could be formed. Here too, as in the physical world, the advantage selected for is calculating outcomes. Great apes know that others know; not only does an ape possess intentions but he knows that others have intentions as well (20). Tomasello says that experiments have demonstrated that apes, given the opportunity, will “manipulate” another’s state of mind (including human agents) in resource competition (21). Great apes have defined gestural communication, especially in terms of directing attention to influence another’s behavior, and although they do not naturally point, they can assume that behavior from human researchers. In other experiments apes copied human behavior when there was no constraint to do otherwise, prompting Tomasello (along with the other forms of social cognition outlined in this paragraph) to conclude that apes indeed think (24).
Tomasello rehearses all of this research to illustrate that apes are not acting mechanically but are making choices in how to act for the best outcome. Other studies (especially with chimpanzees) show that they: will postpone reward-taking under the assumption that waiting will yield a better result; will alter previously successful behavior in new circumstances; will swallow the bitter pill, so to say, if they know there is a reward forthcoming; and will persevere through difficult situations (24). These behavioral examples are equivalent to those found in a three year old human child. Furthermore, apes are aware of their limitations and will self-correct information gathering to achieve an especially prized goal (25).
Regarding human-like thinking, great apes are capable of a number of capacities. First, there is an aptitude to represent previous experience in images and schematics to determine situational pertinence. Second, there is a facility to infer from such representations, to make postulations about others. Third, there is the tendency to review one’s own behavior in a way that permits a recalibration of knowledge and effort, a cognitively supervisory function (30). Tomasello is convinced that our common ancestor with the chimpanzee, as well as our ancestry with australopithecus, was “individually intentional and instrumentally rational” before the advent of distinct human culture and so laid the groundwork for advanced thinking (30).
But the key difference here is that while apes tend to be self-interested with competitive tactics, human beings tend to be helping and caring with cooperative motives. In the hominin line, then, the pressure was for a collective sociality that led to sharing intentions for a common goal and thus the rise of thinking (31). Certainly this was a long evolutionary process, and while there are continuities with great apes (previously outlined), to arrive at the level of collaborative behavior found in human beings, Tomasello agrees that very early in our history, not shared with the great apes, there was a special type of collective behavior selected for.
And this is where we differ from apes and other animals. Tomasello points out that there are many species that will act cooperatively, such as the eusocial insects. But apparently from the ape proclivity for self-interested behavior, including all of its associated capacities mentioned previously, only human beings from our hominin ancestors evolved special capacities to identify and accomplish objectives with a single-minded thought and synchronization (33).
Experiments demonstrate that chimpanzees and even bonobos prefer to eat alone, and if there is a dispute about a piece of food, the dominant individual succeeds. Generally speaking, says Tomasello, food getting among the great apes is a frenzy of power struggles. Tomasello questions whether or not chimpanzee group hunting of monkeys is really a collaborative effort. Instead, he posits, each chimpanzee is most likely out for himself and considers himself, in advance, as the victor in the chase. On the other hand, there is true collaboration in modern human foragers with their child-care, information sharing, teaching, group decisions, and community organization (35-36).
Cooperative behavior probably had its beginnings circa 2mya when first homo species appear because of competition for food resources from an explosion of other hominids (36). Fast forward to the ancestor Tomasello spends most of his time considering, homo heidelbergensis, who appears around 400kya and is an ancestor related to Neanderthals and modern humans. As even Christopher Boehm would agree, heidelbergensis is the first species to engage in serious big game hunting, and this large group practice demands collective activity over individual needs. Foraging, too, becomes more than a mere group activity. Individuals are now linked because of common needs, and with such inter-related working relationships social pressures increase.
Who will be worth working with, and who not? Cheater and free-rider detection and suppression begins. The alpha male’s power diminishes, and so there is a concern for how one appears and hence recursive thinking about what others might be thinking (37-38). Here Tomasello can only provide hypothetical examples, but they are convincing enough. To mark this different behavior, Tomasello looks again to his strength in ape research. Whereas a three year old human child will share a joint goal with a collaborative effort and portion the reward, this is not necessarily so with chimpanzees. Moreover, this three year old (but not a younger child) appreciates division of labor and helping and seems to grasp the notion of obligation to such a degree that if she defaults in the mutual enterprise she will offer an “apology” (40). Chimpanzees, on the other hand, simply gravitate on their own to abundant food sources.
Joint effort implies joint attention, which also means that each actor is attentive to the other’s thinking, and both of these modes of attention probably developed together in human evolution to produce perspective taking (44). Nascent forms of perspective, Tomasello tells us, appears as early as one year in a human infant who can see someone else’s directed attention, but not until a child is four can she understand that there is a difference between her perspective and someone else’s (45). Tomasello’s research reveals that great apes know of another’s intentions but don’t engage in joint intention, that they are aware of and assist in goals but don’t collaborate on such, so that only human beings have the concept of do something together (47). Since the perspective taking ability manifests itself so early in human children (and which is far less pronounced in apes) we can assume that it is an evolved adaptation that helped early human people in collective activities. Accounting for different perspectives is also related to social pressures which gauge how cooperative one is, or not, and helps keep one’s own potential anti-social behavior in check through self-assessment.
What is being considered here, then, are social thinking skills with willful control over self-interest and the desire to manipulate others. Sociality on a collective plane requires advanced supportive communication skills, and we know, Tomasello informs us, that intentional communication is absent in apes, who are mostly limited to gestures of direction and appeal. In contrast, some experiments show that a human child no more than one year old can point to inform, with the key difference that apes are not able to grasp a relevance inference but the child can (51-52). Pointing gestures, however, can be complicated. Pointing to food after a long foraging mission does not equal pointing to food when escaping a predator, so some type of shared context also evolved.
Experiments indicate that in order for a one year old human child to comprehend a pointing behavior he needs, in addition to situation context, some type of history with whoever is pointing. For example, in a situation of toy clean-up with this one year old, if an adult who has been involved in this activity points to a toy, the child will put it away. If, however, another adult, who was neither involved in play or clean-up, enters the scene and points to a toy, the child retrieves the toy and hands it over to the adult (as if the latter were requesting it) (55-56). While apes monitor themselves cognitively, we tend to monitor ourselves socially. We estimate whether or not the person we are communicating with understands, which means that we actually simulate to ourselves how the person might respond (58-59). The implication is that this is an evolutionary advantage built on top of the earlier concern with social self-image. Even a one year old human infant is capable of guessing, and therefore thinking about, another’s point-of-view merely from eye movements (59). Apes are incapable of comprehending many gestures since they do not grasp intention outside of context, and this failing is related to their inability to engage in highly collective, cooperative activities.
Iconic gestures, Tomasello tells us, such as raising a hand as if to eat, more than pointing, require both doer and viewer to imagine something else somewhere else, and so this imaginative-pretense helped human cognition evolve (63). Nonetheless, iconic gesturing could be ambiguously interpreted, and so the combination of such gestures or a gesture linked to a vocalization evolved (66). Even human infants can use a pointing gesture while simultaneously vocalizing, the two clearly linked by the child for the benefit of the viewer. Here, Tomasello says that what arose in our evolutionary history was a common ground between gesturing/vocalization and the recipient, a precursor to language and necessitating some form of abstract thinking. Iconic gestures (head, hand, and body movements) are symbolic in that they are representations of something else or some other action, make propositions, and therefore engage both doer and recipient in shared, abstract thought (70-71). While great apes understand cause and effect, they do not comprehend what another is thinking and hence do not engage in the sophisticated collaboration evident only in human activity.
Such thinking about another’s thinking leads to one intending that another know something (73). Great apes can only think in terms of themselves, the past is in terms of what is wanted or needed now. Early humans, in having the ability to combine iconic gestures and vocalizations to establish shared communication, were trying through perspective taking and other means to imagine what another might be thinking, and the combination of all these aspects of cognition lead to reflective thinking (73-74). There was in early human cognition a concern for another to understand what one was attempting to communicate, which gives evolutionary rise to rationality (76). Such concerns about what others might be thinking lead, Tomasello notes, to normative behavior. Tomasello is not so convinced that any type of so-called Machiavellian behavior prevailed among the homo lineage. Alternatively he posits the multi-faceted cooperative, collective attitude, so prevalent in human history, and evident from studies that distinguish great ape self-interest from human beings helping tendencies (77).
Moving past heidelbergensis and the arbitrary 400kya marker, Tomasello discusses collective intentionality and how early modern human beings, through the creation of distinct groups, generated shared cultural practices and standards, and, importantly, the collective maintenance and transmission of such culture over time (80). While one can argue that chimpanzees and orangutans have culture (e.g., tool use), Tomasello says that these behaviors are not taught cooperatively as in human culture but appear “exploitive” (82) in that there is haphazard and inadvertent copying. The bottom line is that apes are social but human beings are cooperative and, therefore, there is full-fledged human culture. Here Tomasello discusses his notion of the ratchet effect (first published in 1993), which states that while there is fidelity in cultural transmission, any individual might devise an improvement on a practice, which in turn, over time, can itself be improved, and so forth for many generations. At the same time, such fine-tuning of ideas, values, beliefs, and practices leads to more closely-knit groups and the splintering of groups, evident even to this day across nations.
Nevertheless, the movement and shift is from what Tomasello earlier identified in human pre-history, 400kya, as the simple identification of the second person (me-you) to now, at 200kya with anatomically modern homo sapiens, a group identity. Common ground is shared among various individuals to the extent that one can be marginalized if not cooperative. Tomasello suggests that group formation and cultural adhesion will play an important role, eventually, in directing the successors to early modern human beings toward an objective point-of-view, a move from the one-to-one mode of early people to the normative group thinking that fosters emotions such as guilt and shame (87-89).
Some cultural practices, therefore, can turn into institutions, with a sub-group being formed to make certain decisions about food sources or defense (90). There is not much further to go, then, to a band within a group that might have been entrusted to implement more powerful tasks, such as making judgments about behaviors or resolving disputes, with, eventually, the literal and figurative status symbol of such leaders (91). Through these emerging groups linguistic communication began to become dependent on cultural commonality, and, in fact, there is an understanding that in such communication one would employ the common verbal cues of the group to make meaning unequivocal (95). Over time, any such communication gestures, in whatever form, would become reduced and synthesized, Tomasello suggests, so that an outsider would not understand and an insider would have to conform. Inference becomes less dependent on spontaneous action and is now collective and can be passed and modified across generations. The linguistics part of chapter 4 is difficult, but Tomasello seems to say that early modern people had discursive styles of communication that eventually became collaborative, syntactical structures (100).
Complex, symbolic communication gave rise to reasoning abilities and the capacity for one to convince another of her position on an issue or decision. Key here is that such reasoning is collaborative back-and-forth communication. One who argues a point will anticipate the opposition and so have an internal conversation about positions and objections (112). Behind this behavior is the idea that we moved from, in early human beings, unknown factors and people that had to be reasoned out in accord with social standards, to shared norms and linguistic styles which enable one imaginatively to propose a workable theorem about another’s point of view. Thus flowers the feeling of individuality in how a single thinker can step aside from a thought to evaluate it through reason in relation to group culture and subsequently further recalibrate her reasoning in light of any new ideas (114-115). The important evolutionary cognitive and linguistic development of objectivity commits one to reach back over her thoughts in collaborative communication.
In the final chapter (not counting the conclusion) Tomasello arrives at his basic thesis: that because of environmental pressures (competition from other groups, climate variation, and changing supplies of food resources), early human people increased group size and began a movement to more collaboration so that human thinking is cooperation. Here Tomasello deftly surveys a number of other theories (not necessary to reiterate here) that touch on his own, from cultural theorists (Geertz) to evolutionary psychologists (Cosmides and Tooby), with his emphasis on the evolution of culture via cooperation, such as early forms of sociality, division of labor, child care, pair bonding, and group foraging, all of which by 50kya evolved into highly complex joint operations.
The final chapter offers a concise overview, summarized here. In-group competition is not baneful but engenders social behavior such as the perspective taking of another’s viewpoint, though with great apes any such collaboration or communication is essentially for self-survival among aggressive competitors. Through a common goal came shared attention while maintaining one’s own point-of-view and so rose a shared communication style with gestures and pointing which forced inference to bloom on a shared intention (far beyond any such capacity in apes). This type of recursive thinking fostered one to be able to become aware of himself and what he was representing to others. There evolved a set of norms and practices so that different (unknown) members of the same group could work together while distinguishing themselves from members of other groups, hence the rise of group personality. Early forms of shared intentions existed in Africa prior to the Neanderthal break off. Later, intentions laid the ground work for cultural differences with the spread of groups out of Africa. Even sapiens cognition could vary depending on local needs and practices, but all such distinct groups evolved culture in a cumulative manner that was also tied to cognitive development.
Tomasello makes a final point about the role of ontogeny. While the evolved ontogeny of cognitive adaptations is evident (from behaviors of human infants he discussed earlier), it is not enough, for a human child needs the in-place cultural context to develop fully any set of shared intentionality and collective, collaborative group thinking. In conclusion, human social thinking is like that evolved in no other species and is essentially cooperative, recursive, and objective in nature.
- Gregory F. Tague
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