The Machiavellian intelligence theory: what exactly is it?

This theory explains how competition between individuals could have generated larger brains.

The evolution of the human brain in comparison with other animals, particularly primates, is still a mystery under constant investigation. It has been the subject of much debate since the English naturalist Charles Darwin presented his theory of evolution to the world in 1859.

One of the strongest assumptions that attempts to explain this difference is the theory of Machiavellian intelligence, which relates the evolution and development of the brain to the level of social with the level of social development of each species.

What is the theory of Machiavellian intelligence?

Unlike other animals, humans have undergone infinitely superior brain development, with the cognitive and behavioral consequences that this entails. Even compared to primates, the human brain is considerably larger and more complex, the human brain is considerably larger and more complex than that of primates..

Although the cause of such abysmal differences in brain development has not yet been established with complete certainty, there are many theories that attempt to explain this phenomenon that gave "homo sapiens" the ability to develop a much more complex mind.

Some of them propose that brain development is a response to the ability to adapt to changes or alterations in the environment. According to these hypotheses, the subjects with more adaptive capacity and who were able to overcome and survive the adversities of the environment, such as environmental or meteorological conditions, have managed to spread their genes, resulting in a progressive brain development..

However, there is another theory with much more support from the scientific community: the theory of Machiavellian intelligence. Also known as social brain theory, this assumption postulates that the most important factor in brain development is social competition.

Broadly speaking, this means that those individuals with more social skills were more likely to survive. Specifically, these skills considered as Machiavellian refer to social behaviors such as the ability to lie, cunning and insight. In other words, the more astute and socially skilled subjects achieved much greater social and reproductive success. achieved much greater social and reproductive success.

How was this idea forged?

In the research work "Social behavior and evolution of primates" published in 1953 by researchers M. R. A. Chance and A. P. Mead, it was suggested for the first time that in social interaction, understood as part of a competitive environment for achieving status within a social structureThe key to understanding brain development in hominid primates could be found in social interaction, understood as part of an environment of competition for status within a social structure.

Later, in 1982, the Dutch researcher specialized in psychology, primatology and ethology Francis de Waal, introduced the concept of Machiavellian intelligence in his work Chimpanzee politicsin which he describes the social and political behavior of chimpanzees.

However, it was not until 1988 that the theory of Machiavellian intelligence as such was elaborated. Thanks to the antecedents that relate the concepts of brain and social cognition and Machiavellian intelligence, psychologists Richard W. Byrne and Andrew Whiten, researchers at the University of St. Andrews in Scotland, carried out a compendium of research published under the name "Machiavellian Intelligence: Social Experience and the Evolution of Intellect in Monkeys, Apes and Humans".

In this work the researchers present the hypothesis of Machiavellian intelligence, which attempts to convey the idea that the mere need to be more insightful and astute than other individuals generates an evolutionary dynamic in which Machiavellian intelligence, in the form of the use of social cognition skills, would give rise to a social advantage and a social advantage, would give rise to a social and reproductive advantage..

Brain development and social intelligence

Although at first glance it may seem complicated to associate the level of intelligence or brain development to a phenomenon of a social nature, the truth is that the hypothesis of Machiavellian intelligence is supported by neuroanatomical evidence. is supported by neuroanatomical evidence..

According to this theory, the cognitive demands and requirements due to an increase in social interactions, which in turn comes from the gradual increase in the number of individuals in a society, led to a growth in the size of the neocortex, as well as its complexity.

From the perspective of the Machiavellian intelligence hypothesis, the increase in the complexity and size of the neocortex is a function of the variability of the behaviors that the subject can carry out in that the subject can carry out in interaction with his society. This specification is of particular relevance as it explains the differences in neocortex development between primates and humans compared to other animal species.

In addition, numerous papers and studies support the idea that the dimensions of the neocortex increase as the size of the social group increases. as the size of the social group increases. Moreover, in the specific case of primates, the size of the amygdala, an organ traditionally linked to emotional responses, also increases as the size of the social group increases.

This is due to the fact that the correct development of emotional modulation and regulation skills is necessary for social integration and success, hence the consequent increase in the size of the amygdala.

The Gavrilets and Vose study

In order to test this hypothesis, the researchers from the University of Tennessee, USA, S. Gavrilets and A. Vose conducted a study in which, through the design of a mathematical model, the development of people's brains could be simulated based on the theory of Machiavellian intelligence.

To do this, the researchers took into consideration the genes responsible for learning social skills.. They came to the conclusion that the cognitive abilities of our ancestors increased significantly over only 10,000 to 20,000 generations, a very short time span considering the history of mankind.

This study describes brain and cognitive development in three different phases that occurred throughout human history:

• First phase: the social strategies created were not transmitted from individual to individual.
• Second phase: known as the "cognitive explosion" phase.In this period, a high point in the transmission of knowledge and social skills was manifested. It was the time of greatest brain development.
• Third phase: called "saturation" phase.. Due to the enormous expenditure of energy involved in the maintenance of an increasingly larger brain, its growth stopped, remaining as we know it today.

It is necessary to specify that the authors themselves report that their results do not necessarily prove the hypothesis of the theory of Machiavellian intelligence, but that the mechanisms or phenomena that produced this growth may coincide with the historical moment in time in which it is hypothesized that they occurred.