So many people
are talking about Artificial Intelligence, I thought it would be useful to see
what psychologists think about natural intelligence. It’s a term that we all
think we know the meaning of, but what is it that those people working in that
field would be able to identify or recognize as intelligence?
Like all good
philosophy essays, let’s start with a definition of intelligence. Intelligence
is: “the ability to acquire and apply knowledge and skills”. Or: “the ability
to solve complex problems or make decisions with outcomes benefiting the actor”.
Or: “the capacity or ability to acquire, apprehend, and apply knowledge in a
behavioural context”. So, we’re looking at acquiring information and applying
that information.
It’s also been
suggested that intelligence gives humans the cognitive abilities to learn, form
concepts, understand, and reason, including the capacities to recognize
patterns, innovate, plan, solve problems, and employ language to communicate.
In psychology,
there have been various theories about what intelligence actually is and
attempts to measure it.
Psychometric
theories treat intelligence as a composite of abilities measured by mental
tests that measure reasoning ability and memory. Tests can be given to people
and a numerical result can be produced.
Spearman found
that people who do well on one type of test generally do well on other types.
Using factor analysis, he suggested there were two kinds of factor underlying
all differences in test scores. Firstly, there was a general factor, which he
labelled ‘g’, and a second factor specifically related to the type of task.
On the other
hand, Thurstone proposed seven ‘primary mental abilities’. They were: verbal
comprehension; verbal fluency; number; spatial visualization; inductive
reasoning; memory; and perceptual speed.
Vernon and
Cattell modelled intellectual abilities as hierarchical, with g (general
ability) at the top, and specific abilities below. Cattell also suggested that
general ability can be subdivided into ‘fluid’ and ‘crystallized’, where fluid
abilities are the reasoning and problem-solving abilities measured by tests,
and crystallized abilities include vocabulary, general information, and knowledge
about specific fields.
Cognitive
psychologists didn’t go along with these ideas, they thought that it was
important to understand the processes underlying intelligence. They assumed
that intelligence comprises mental representations (such as propositions or
images) of information and processes that can operate on such representations.
Hunt, Frost,
and Lunneborg suggested that basic cognitive processes are the building blocks
of intelligence.
Many of the
experiments assumed that humans processed information sequentially or serially.
However, they may well process information in chunks and in parallel. And there
may be cultural differences.
Cognitive-contextual
theories looked at how cognitive processes operate in various settings. Gardner
proposed a theory of ‘multiple intelligences’, including linguistic,
logical-mathematical, spatial, musical, bodily-kinaesthetic, interpersonal, and
intrapersonal intelligence.
Sternberg
proposed a ‘triarchic’ theory. He thought that musical and bodily-kinaesthetic
abilities were talents rather than intelligences. Sternberg’s three integrated
and interdependent aspects of intelligence were: practical (the ability to get
along in different contexts), creative (the ability to come up with new ideas),
and analytical (the ability to evaluate information and solve problems).
Biological
theories of intelligence suggest that understanding intelligence is only
possible by identifying its biological basis. It’s looking at neurons.
There have been
studies of different areas of the brain. For example, Levy and others found
that the left hemisphere is superior in analytical tasks, such as are involved
in the use of language, while the right hemisphere is superior in many forms of
visual and spatial tasks. Overall, the right hemisphere tends to be more
synthetic and holistic in its functioning than the left. Remember that the
corpus callosum links the two halves of the brain, so work was done on patients
whose corpus callosum had been severed. Levy and Sperry found that the left
hemisphere of the brain functioned better with patterns that are readily
described in words but are difficult to discriminate visually. Whereas the
right hemisphere was more adept with patterns requiring visual discrimination.
Eysenck and
others looked at brain waves and speed of response in people taking
intelligence tests. Some researchers
found a relationship between brain waves, and scores on a standard psychometric
test of intelligence.
Others have
looked at blood flow in the brain, which indicates which areas of the brain are
being used. Haier found that people who perform better on conventional
intelligence tests often show less activation in relevant portions of the brain
than do those who perform less well.
There have been
a number of studies of children showing how intelligence develops. The
outstanding researcher in this area is Piaget. His four stages of cognitive
development were: sensorimotor intelligence; preoperational thinking; concrete
operational thinking; and formal operational thinking.
You might ask
what impact environment has on intelligence? It does seem that intelligence
runs in families, and according to Plomin, “recent genome-wide association
studies have successfully identified inherited genome sequence differences that
account for 20% of the 50% heritability of intelligence”. However, there is no
single gene for intelligence. And, we know from epigenetics that through a
process called methylation, genes can be turned on or off. DNA methylation is
influenced by diet, exercise, stress, relationships, thoughts, nutritional
status, toxins, sleep, infections, etc. So, yes, environment can affect a
person’s intelligence.
What do
intelligence (IQ) tests measure? Because there is no complete definition of
intelligence, it would seem that IQ tests simply measure what IQ tests measure!
It’s worth
noting that people also talk about Emotional Intelligence (EI), and there are
EQ tests to measure how emotionally intelligent a person is. Emotional
Intelligence is usually described as a person’s ability to perceive, use,
understand, manage, and handle emotions. The name most associated with EI is
Daniel Goleman. Some research has found that people with high EI have greater
mental health, job performance, and leadership skills. There are debates about
whether EI is really a form of intelligence or something else.
What can AI
developers learn from natural human intelligence? That’s difficult to answer.
Clearly people like Thurstone, Cattell, and Gardner (and many others) came up
with lists of things that make up human intelligence and these lists might be
helpful for AI developers. However, like in all things, there have been many
different approaches to the question of what is intelligence? What might be of
interest is an idea from Carol Dweck in her book called Mindset: The New
Psychology of Success. The book suggests that some people believe their
success is based on innate ability; these people are said to have a ‘fixed’
theory of intelligence (ie a fixed mindset). Other people believe their success
is based on hard work, learning, training, and doggedness; these are said to
have a ‘growth’ or an ‘incremental’ theory of intelligence (growth mindset).
And everyone else is meant to be somewhere on a continuum between the two
extremes. Perhaps the one thing to takeaway is that a successful AI needs to
have a growth mindset.