The social function of intelligence

Why are humans able to communicate with each other using symbolic language? Why can we follow and apply the rules of inductive and deductive logic? Why can we manipulate numbers? Why can some people understand physics?!!! All our cognitive abilities developed in order to solve problems in our environment - and the biggest problems our ancestors faced were each other!

Nick Humphrey wrote a paper called 'The social function of intellect'. The following is an abridged excerpt from that piece of work.

'Some years ago I made a discovery ... a cage is a bad place in which to keep a monkey. I was studying the recovery of vision in a rhesus monkey, Helen, from whom the visual cortex had been surgically removed ... When, at length, five years after the operation, she was released from her cage and taken for walks in the open field at Madingley her sight suddenly burgeoned and within a few weeks she had recovered almost perfect spatial vision [which had been absent since the operation]'(Humphrey, 1976, p. 308).

Since that enlightening experience, Humphrey looked anxiously through the wire mesh of monkey's cages in research settings - in particular he mentions those of Robert Hinde. The following describes what he saw:

'They live in social groups of eight or nine animals in relatively large cages. But these cages are almost empty of objects, there is nothing to manipulate, nothing to explore ... So I looked - and seeing this barren environment, thought of the stultifying effect it must have on the monkey's intellect. And then one day I looked again and saw a half-weaned infant pestering its mother, two adolescents engaged in a mock battle, an old male grooming a female whilst another female tried to sidle up to him, and I suddenly saw the scene with new eyes; forget about the absence of objects, these monkeys had each other to manipulate and explore' (Humphrey, 1976, p. 308).

Higher primates are highly social animals and living in an environment with frequent social interactions can be highly problematical. To be able to cooperate with others is very beneficial as it helps preserve the group structure, but it is also beneficial to be able to exploit and out-manoeuvre others for your own benefit. These opposite forms of interaction require in-depth calculations. For example, primates need to be capable of determining the possible consequences of their own behaviour; evaluate the probability of various reactions to their behaviour by others; and to then calculate the possible benefits versus losses of various actions by all parties to the interaction. Such complicated social skills require high intellectual abilities.

Evolutionary pressures shaped the human mind to move from our ancestor's examining their relationship to static things in the physical environment, to being able to examine and modify their social environment as well. Our intelligence is adapted for the social milieu, as civilisation has been too short to have had any important evolutionary consequences; although we are capable of dealing with non-social problems. In saying that, it is evident that we do have cognitive biases that allow us to process social information much better that non-social information.

The Watson selection task shows how our information processing abilities are dependent on content (Cosmides & Tooby, 1997).
An example of such a task might involve participants being told the rule 'if there is a vowel on one side of the card, there must be an even number on the back' and they are then showing the following four cards.

They were then asked what two cards they would turn over to confirm whether the rule is true. Most people find this task quite difficult, and the majority choose the wrong cards. Cosmides and Tooby (1997) report correct response rates as low as 5-25%. Which ones would you turn over? (Solution at bottom of page) However, if the content on the cards is changed so that the participants have to solve a reasoning task based on social interactions - such as someone cheating on a social contract, then Cosmides and Tooby (1997) report that about 65-80% of people will choose correctly. This shows that our ability to reason works best when the content of the task is based on social interactions.

Solution: The cards that you should turn over are the E and the 7. If the E does not have an even number or the 7 has a vowel on the back, then the rule is disproved. The rule only gives a condition specific to cards with vowels. It does not say that a consonant cannot have an even number, and neither does the rule say that an even numbers can only be on the back of vowels.

Darwin's Theory of Evolution

Environment of Evolutionary Adaptation


Sexual Selection

References and Bibliography

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