Being smart is good. This is something that everyone knows, because it means that having a high level of intelligence helps us to deal effectively with the different events in life.

However… what exactly is being smart? What do we mean by intelligent? When it comes to answering these questions, doubt appears, the answer being neither simple nor insubstantial.

In fact, the study of intelligence is a complex phenomenon that has been extensively and frequently explored from the perspective of psychology, there being a large number of ways of understanding what and how intelligence is and having raised numerous theories of human intelligence throughout history .

Intelligence: a complex concept

In a generic way and without going into detail regarding what forms part of it, we can consider intelligence as the capacity or set of mainly cognitive abilities that allow us to adapt to the environment, solve the problems that it poses and even successfully anticipate them. However, the different authors who have dealt with and studied intelligence have found different definitions of this concept , some contradicting each other while others are complementary.

Different approaches have been used to carry out these studies, with some taking a more experimental, genetic or functional approach. One of the approaches has been focused on determining the components of intelligence in order to understand it, this being the focus of the factorial theories on which this article is based.

Two major groups of theories

Although, as we have said, there are various ways of classifying the enormous variety of theories regarding what we consider intelligence , one of the clearest is the one that is most divisive between the different conceptualizations: whether intelligence is one or, on the contrary, there are various types of intelligence.

A unitary intelligence

The first studies referring to intelligence and intellectual capacity worked under the assumption that intelligence is a single general, unchangeable and genetically determined capacity. Through these theories, psychometric tests have been elaborated that value intelligence from its reflection in standardised tests , measuring through them the IQ or IQ. According to these theories, then, intelligence was unifactorial

Capability set

There are other theories that stipulate that intelligence is not a single ability, but a set of skills and abilities independent of each other. This explains why there are geniuses in some aspects such as music and art who have a limited logical capacity, or eminencies on an intellectual level who are incapable of projecting such knowledge or understanding the reactions of others. It is this type of theories, multifactorial, that are most considered today .

Main theoretical proposals

Whether considered a single or multiple capability, the truth is that research on this subject has been extensive and has allowed the construction of various theories. Some of the most considered throughout history are the following.

First approximations: Binet

The name of Alfred Binet is especially known for having been the creator of the first scale for measuring intelligence . This author, who considered intelligence to be a unique ability, was one of the first to explore the concept of mental age as the age at which most subjects are capable of performing or solving a given problem. He believed that skills and abilities could be improved with education and training.

The concept of mental age would be used by this author as a measure of intelligence. After him, William Stern would link this mental age to the chronological age in order to be able to evaluate in a comparative way the level of intellectual development and finally with all this Terman would end up creating the concept of Intellectual Quotient or IQ.

Spearman’s bifactorial theory

One of the first theories of intelligence, Spearman proposes in his bifactorial theory of intelligence that there is a general intellectual capacity or G Factor, which is common to all the activities we carry out.

However, depending on the type of activity we do, we will have to apply specific skills to carry it out, specific skills that are called Factor s. While the g-factor is hereditary and unchangeable, specific skills would be improvable through learning and education.

Cattell’s theory of intelligence

One of the best known theories of intelligence is that of Raymond Cattell . In his theory this author interprets, partly based on the bifactorial theory, that intellectual capacity is configured by two types of intelligence: fluid and crystallised. While fluid intelligence corresponds to reasoning and the general capacity to adapt to new situations, without learning influencing the action taken, crystallised intelligence refers to the capacity to apply the knowledge learned throughout life.

On the other hand, Cattell did not believe that the g-factor was a reflection of a natural process that actually occurs in the human brain, but that it would simply be a statistical product caused by the fact that by measuring it is not possible to isolate well the really existing processes.

It also explores its development throughout life, stating that crystallized intelligence varies throughout life, increasing with the accumulation of experience, while fluid intelligence would remain fixed after brain maturation during adolescence.

Vernon’s hierarchical model

One type of theory that has also worked in the field of intelligence is that of hierarchical models, whose main representative is Philip Edward Vernon . These models are based on the idea that the specific factors (those pertaining to the concrete activities we carry out) are the bases of superior abilities, which form hierarchies until reaching general ability or intelligence. The last two divisions before reaching factor g would be the verbal-educational and spatial-motor factors, which the author links to a specific hemisphere.

In addition to this, Vernon’s model proposes that intelligence can be understood in three parts: A, B and C. Intelligence A understands intelligence as the possibility to learn and adapt, intelligence B corresponds to the level of ability demonstrated in behaviour and intelligence C refers to the score obtained in intelligence tests.

Thurstone’s theory of primary skills

As we have previously indicated, not all authors agreed that intelligence is a unique capacity, with authors considering mental capacity as a composite and multifactorial element. Louis Leon Thurstone did not believe in the existence of a general factor of intelligence, but rather that different independent factors in its functioning but linked to each other allow us to guide behaviour in order to be able to face the demands of the environment.

That is why he developed the theory of primary mental aptitudes, one of the first multifactorial theories of intelligence, in which through factorial analysis he found various aptitudes that allow the correct adaptation to the environment. Specifically, Thurstone refers to the capacities of verbal comprehension, verbal fluency, memory, spatial capacity, numerical capacity, agility/perceptive speed and logical reasoning.

Guilford’s Theory of Intellectual Structure

Another author who opposed the idea of a single intelligence was Joy Paul Guilford. This author presents a theory of intelligence based on a three-dimensional model , in which intellectual operations, contents and products of the intellect are taken into account when evaluating any intellectual factor from a perspective similar to the cognitive one.

The contents of the intellect would refer to the type of information with which the intellect operates from stimuli, and could be figurative, symbolic, semantic or behavioural content.

Mental operations are understood as the processes from which information is worked , being these operations cognition, memory, evaluation and convergent and divergent production. Finally, mental operations reflect a series of results, which may take the form of units of information, classes or concepts, relations, systems, information transformations and a work of association or implication between stimuli and information.

In addition to this operational consideration of mental processes, the author links intelligence to the capacity to generate new strategies and solutions to the problems posed beyond the typical ones, however useful they may have been. Thus, intelligence is also related to creativity and divergent thinking .

Sternberg Triarchic Theory

We cannot fail to see that the theories put forward focus largely on how intelligence is structured as something internal, regardless of where it is applied. Robert J. Sternberg also took this fact into account, elaborating his triarchic theory from which it is considered that there are three types of intelligence.

The first of these is analytical intelligence, which corresponds to the traditional idea of intelligence as the capacity to acquire, codify and store information, being able to carry out a theoretical analysis of the situation.

The second of Sternberg’s intelligences is practical intelligence, which refers to the capacity of contextualization, that is, the capacity to select the most adaptive and appropriate behavior or strategy according to the needs and resources derived from the environment. Theoretically, it would be very similar to the crystallized intelligence proposed by Cattell and other authors based on him.

Finally, for Sternberg there is one more intelligence , the creative intelligence dealt with in his experiential sub-theory through which we have the capacity to face new situations by working and elaborating strategies from the information acquired throughout life.

Gardner’s Theory of Multiple Intelligences

Howard Gardner has been a critical figure with the idea of the presence of a single intelligence and the fact that it can be measured by IQ. In fact, it must be taken into account that in the classical intelligence tests, abilities of a logical and verbal nature are essentially measured, and the importance of other abilities in being able to adapt to the environment is not observed.

This author considers that it is not possible to speak of a single skill that can be qualified as intelligence. He considers that intellectual capacity and performance are due to a conglomerate of mental abilities common to all to a greater or lesser extent, establishing different types of intelligence to be applied in different contexts. Specifically, although he is open to the possibility that more exist, Gardner highlights new; logical-mathematical, linguistic, kinetic-corporal, intrapersonal, interpersonal, spatial, musical, and naturalistic intelligence.

  • You can learn more about Gardner’s theory in this article: “Gardner’s Theory of Multiple Intelligences”

Other theories

There are many other theoretical proposals of intelligence. For example, emotional intelligence put forward by Daniel Goleman is a concept increasingly used among the general population.

This theory considers that the ability to identify, manage, modify and manipulate one’s own and other people’s emotions is a form of intelligence to be taken into account. Currently, social intelligence is also being discussed, although it could be included within interpersonal intelligence.

Bibliographic references:

  • Hernangómez, L. and Fernández, C. (2012). Personality and differential psychology. Manual CEDE de Preparación PIR, 07. CEDE: Madrid.
  • Martin, M. (2007). Historical and conceptual analysis of the relations between intelligence and reason. Spain: Universidad de Málaga.