The work represents the interesting findings of a British research project determined to study the connection between the development of the modern human / homo mind and his ever increasing social group. It defines itself within the transdisciplinary framework of psychology and archaeology, but it tends to drive heavily on the latter part, which drags the book out a little longer than necessary, perhaps, for the average reader. The thesis, however, is clear and simple: due to a variety of factors described at length (such as tool-making, manipulating fire, changes in the environment etc), the number of hominins that had to group together increased. There is a direct correlation between this and the sizes of their brains, which should not come as a surprise, since we are dealing with new cognitive loads, new approaches to grooming, and language.

Interesting quotes to reflect on include:

Emotional closeness indexed in this way turns out to correlate with frequency of contact: the more often you contact someone, the more emotionally close you feel to them. One obvious implication of this finding is that if you interact less with someone for some reason – perhaps because you move away to another town and can’t see them so easily anymore – then your relationship with them, as measured by your emotional closeness, is likely to deteriorate quite rapidly

Emotional closeness and altruism go hand in hand. [proximity is everything]

Friendship relationships are fragile and decay rapidly if they are not reinforced.

Family relationships were incredibly robust in the face of failure to interact.

Children first acquire this ability [mentalize] around the age of five years, when they realize for the first time that other people have minds of their own.

Engage in true fictional play […] This is an important capacity that sets in train the possibility of something far more important than children’s games: it is what eventually makes culture possible. [what happens if they don’t, due to technology?]

Evolution occurs when natural selection acts on differences between individuals because those differences are correlated with fitness.

Evolving a bigger brain does not come for free and so must have a very strong selection pressure in its favour. The social brain hypothesis tells us exactly what that selection pressure was: the need to create large coherent social groups that involve a proportionally large number of relationships.

Physical exercise triggers the release of endorphins as a natural consequence of the pain created by the activity.

Instead of the rules of social behaviour being determined and passed on by a social institution they are worked out by the individual.

Humans turn out to lie exactly half way between monogamous primates (like the gibbons) and polygamous one (like baboons and chimpanzees).

Social life takes place in our minds, in our imaginations. We constantly think about others from our various networks.

Raiding is invariably a response to limited resources and populations close to carrying capacity.

Infants who now, thanks to larger brains, are born ever more helpless and need nurturing for much longer.

Social life is not based on calories alone, but on the relationships that emerge when things are made, exchanged, used and kept.

[infant dependency -> role for grannies -> larger community size]

The key capacity of humans is to live in the imagination.

A tool allows us to pay attention to the detail, to study something that might have taken five or ten minutes to make, but which represents hominin technology across half a million years. And this attention that we bring to the attention that they applied to the job in hand makes this a supremely social techology.

There would have been a fundamental shift in the means of communication as the pressure of numbers of interaction partners squeezed the time available.

Crucial in the origin of language, it seems, are our abilities to consider and reflect on ourselves. Many animals are self-aware. […] Second order intentionality, being aware of another’s mind, is only reached by humans and a few well tutored captive chimps.

The handaxes involve a complexity of design requiring a mental overview, and, as the maker has to integrate the manufacturing steps through time, it can be said that there is a kind of operational syntax. There was certainly some kind of communication centered on paying close attention to others and employing visual cues.

Some form of language, not necessarily speech, was needed if a hominin was to have more than second order intentionality and a formal theory of mind.

Social cognition is expensive. Where the ecology favours larger groups, there is a ‘strain on the brain’ – what we refer to as cognitive load. Over the course of 2 million years, evolution favoured ever larger brains in the genus Homo.

Although hunter-gatherer societies eschew any social distinctions (everyone is equal), charismatic leaders have come to play an especially important role in all post-Neolithic societies and in the doctrinal religions that these gave rise to. At one level, they provide leadership; at another, they provide a focus around which the community can gather.

It is a feature of religious belief that it can rouse intense emotional commitment irrespective of the actual beliefs to which people sign up. It is as though the spirit world has a peculiar emotional hold over the human mind.

Emotional closeness indexed in this way turns out to correlate with frequency of contact: the more often you contact someone, the more emotionally close you feel to them. One obvious implication of this finding is that if you interact less with someone for some reason – perhaps because you move away to another town and can’t see them so easily anymore – then your relationship with them, as measured by your emotional closeness, is likely to deteriorate quite rapidly.

Emotional closeness and altruism go hand in hand. [proximity is everything]

Friendship relationships are fragile and decay rapidly if they are not reinforced.

Family relationships were incredibly robust in the face of failure to interact.

Children first acquire this ability [mentalize] around the age of five years, when they realize for the first time that other people have minds of their own.

Engage in true fictional play […] This is an important capacity that sets in train the possibility of something far more important than children’s games: it is what eventually makes culture possible. [what happens if they don’t, due to technology?]

Evolution occurs when natural selection acts on differences between individuals because those differences are correlated with fitness.

Evolving a bigger brain does not come for free and so must have a very strong selection pressure in its favour. The social brain hypothesis tells us exactly what that selection pressure was: the need to create large coherent social groups that involve a proportionally large number of relationships.

Physical exercise triggers the release of endorphins as a natural consequence of the pain created by the activity.

Instead of the rules of social behaviour being determined and passed on by a social institution they are worked out by the individual.

Humans turn out to lie exactly half way between monogamous primates (like the gibbons) and polygamous one (like baboons and chimpanzees).

Social life takes place in our minds, in our imaginations. We constantly think about others from our various networks.

Raiding is invariably a response to limited resources and populations close to carrying capacity.

Infants who now, thanks to larger brains, are born ever more helpless and need nurturing for much longer.

Social life is not based on calories alone, but on the relationships that emerge when things are made, exchanged, used and kept.

The key capacity of humans is to live in the imagination.

A tool allows us to pay attention to the detail, to study something that might have taken five or ten minutes to make, but which represents hominin technology across half a million years. And this attention that we bring to the attention that they applied to the job in hand makes this a supremely social techology.

There would have been a fundamental shift in the means of communication as the pressure of numbers of interaction partners squeezed the time available.

Crucial in the origin of language, it seems, are our abilities to consider and reflect on ourselves. Many animals are self-aware. […] Second order intentionality, being aware of another’s mind, is only reached by humans and a few well tutored captive chimps.

The handaxes involve a complexity of design requiring a mental overview, and, as the maker has to integrate the manufacturing steps through time, it can be said that there is a kind of operational syntax. There was certainly some kind of communication centered on paying close attention to others and employing visual cues.

Some form of language, not necessarily speech, was needed if a hominin was to have more than second order intentionality and a formal theory of mind.

Social cognition is expensive. Where the ecology favours larger groups, there is a ‘strain on the brain’ – what we refer to as cognitive load. Over the course of 2 million years, evolution favoured ever larger brains in the genus Homo.

Although hunter-gatherer societies eschew any social distinctions (everyone is equal), charismatic leaders have come to play an especially important role in all post-Neolithic societies and in the doctrinal religions that these gave rise to. At one level, they provide leadership; at another, they provide a focus around which the community can gather.

It is a feature of religious belief that it can rouse intense emotional commitment irrespective of the actual beliefs to which people sign up. It is as though the spirit world has a peculiar emotional hold over the human mind.