Personality types - theories and defining characteristics

Personality is a complex construct that refers to the set of psychological and behavioural characteristics that define an individual. It shows itself in the way a person thinks, feels and acts, thereby influencing social interactions and life choices. The specialist literature has developed numerous theories in order to describe and classify these traits, each of them offering a unique perspective on human diversity. From Carl Jung’s theory of personality types, which formed the basis of the Myers-Briggs instrument, to the model of the five big traits (Big Five), these theoretical frameworks help us understand the complexity of human behaviour.

Each of these theories underlines the importance of individual traits and typologies, offering a useful instrument for personal and professional development. For example, the Big Five theory, which identifies the traits of openness, conscientiousness, extraversion, agreeableness and neuroticism, has been validated through empirical studies and is widely used in the field of psychology. In contrast, psychodynamic approaches, such as those proposed by Freud, emphasise unconscious influences and the early development of personality. These varied perspectives allow us to explore not only personality typology, but also the way these types influence self-perception and relationships with others.

Carl Jung, one of the most influential psychologists of the 20th century, developed a theory of personality that emphasises psychological types and the way people use their psychic energy in order to interact with the world. Jung was interested in the way the individual perceives and judges reality and he proposed two fundamental dimensions of personality: the attitudes (introversion and extraversion) and the psychological functions (thinking, feeling, intuition and sensation). His theory became the basis for many later approaches to personality, including the famous Myers-Briggs test.

Jung introduced the idea of introversion and extraversion as two fundamental ways in which individuals direct their attention and their energy. Introverted people tend to be more reserved, oriented towards their inner world and preoccupied with reflecting on their own thoughts and feelings. They prefer solitary activities and need time to recharge after social interactions. Extraverts, on the other hand, are oriented towards the outer world, seeking social interactions and dynamic activities. They draw their energy from the company of others and feel revitalised in active social settings.

In addition to these two fundamental attitudes, Jung identified four psychological functions through which people perceive and process the information around them: thinking, feeling, intuition and sensation. The function of thinking is based on logic and reason, analysing information in an objective way in order to make decisions. The function of feeling involves the emotional evaluation of experiences, emphasising values and affects. The function of sensation is based on the concrete perception of reality through the senses, being concerned with details and observable facts. In contrast, the function of intuition is linked to perceiving reality in a more abstract way, relying on subjective understandings and on the big picture.

Combining these attitudes and functions leads to eight distinct personality types, each with a unique way of interacting with the world. For example, an individual with the extraverted-thinking personality type will tend to be logical, objective and action-oriented in the external environment, while an introverted-intuitive one will have a more reflective approach and will rely on intuitions and deep understandings of reality. Carl Jung’s theory of personality types has significantly influenced modern psychology and has offered a valuable understanding of human diversity in terms of the way individuals perceive and interact with the world around them.

Hippocrates, known as the father of medicine, proposed a theory of personality based on the balance of the four bodily humours: blood, yellow bile, black bile and phlegm. These humours were considered responsible for the physical and mental health of the individual, and Hippocrates associated each humour with a certain type of temperament. The four personality types identified by Hippocrates are: sanguine, choleric, melancholic and phlegmatic.

The sanguine is characterised by an energetic, cheerful and optimistic personality. People with this type of temperament tend to be extraverted, sociable and enthusiastic, having a lively nature and loving the company of others. Sanguine people adapt quickly to change and have a high capacity to cope with challenges. In the theory of humours, this temperament was associated with a predominance of blood, which explains their active and exuberant nature.

The choleric is defined by a dominant, determined and impulsive temperament. People with this type of personality are often ambitious, competitive and oriented towards reaching their goals. Choleric people have an inclination towards leadership, but they can sometimes be irritable and aggressive in the face of obstacles. This personality type was linked to an excess of yellow bile, which, according to Hippocrates’ theory, contributed to their strong and fearless nature.

The melancholic is characterised by an introspective, sensitive and analytical personality. These individuals tend to be more reserved, having a reflective nature and an inclination to analyse their thoughts and feelings. Melancholic people are often perfectionist and creative, but they can have a predisposition towards sadness and anxiety. Hippocrates associated this temperament with an excess of black bile, which leads to a contemplative and, at times, melancholic disposition.

The phlegmatic is described through a calm, balanced and patient personality. People with this type of temperament are peaceful, loyal and tolerant, avoiding conflict and preferring to keep a harmonious atmosphere around them. Phlegmatic people tend to be well balanced emotionally, but they can sometimes seem detached or lacking in energy. Hippocrates associated this temperament with a predominance of phlegm, which gives this personality a stable and quiet nature.

Personality disorders are a set of maladaptive patterns of thinking, behaviour and emotion that deviate significantly from the cultural and social expectations of the individual. These disorders are considered pathological because they affect the person’s daily functioning, interpersonal relationships and adaptation to the environment. The main characteristic of personality disorders is the rigidity and the constancy of the problematic behaviour in the long term, which leads to significant suffering or dysfunction in important areas of life, such as work, family and social life.

In the DSM-5 (the Diagnostic and Statistical Manual of Mental Disorders, fifth edition), personality disorders are classified into three groups (clusters) based on common traits:

Cluster A: eccentric or odd personality disorders

Cluster B: dramatic, emotional or unpredictable personality disorders

Cluster C: anxious or fearful personality disorders

These disorders are chronic and influence all aspects of a person’s life, often requiring psychotherapeutic interventions and, in some cases, pharmacological treatment in order to help the individual function better in society.