The first four essays outlined an overview map of the brain. The reticular system, brainstem, limbic system, cerebral cortex, and cerebellum are the brain’s five major functional units. Each plays an important role in human nature.
This essay outlines a well-known map of the mind – Carl Jung’s personality model. It fits well with our brain map, and nicely illustrates each system’s role in our lives.
Jung was a Swiss psychiatrist, a student of Freud’s, and a leader in the early psychoanalytic movement. He later broke with Freud, and developed a somewhat different view of the mind, which remains influential today.
According to Jung, we have four basic “psychological functions,” which he called intuition, sensation, feeling, and thinking. These are our major personality divisions, the basic dimensions of human nature. A fifth force balances and integrates them.
Intuition is at the core. Here is deep spiritual awareness, and the nonspecific spark of illumination that is the essence of intuition.
Sensation is Jung’s label for our instinctive nature, including simple sensory and body awareness, as well as basic drives.
Feeling is his label for social emotions, and their expression in our relations with others.
Thinking refers to the intellect, the realm of knowledge and ideas.
Individuation is a balancing and integrating force. Jung emphasized its role in personal growth and mental health.
These five functions correlate well with reticular, brainstem, limbic, cortical, and cerebellar functions, as outlined below.
In daily life, all five systems are always active, generating thoughts, feelings, sensations, and intuitions – all coordinated and integrated in a more or less unified whole. One function may predominate now, and others later, but all are continually active. Each plays a major role in who we are and what we do.
According to Jung, every person relies on one function more than the others. This basic personality preference is determined by both genetic (inborn temperament) and environmental (childhood learning) factors. One’s psychological type is established during childhood, and remains the same throughout life.
So sensation types, Jung said, are ruled by their instincts, by physical pleasures and pains, by “purely sensuous reality.” Feeling types are “good social mixers,” most concerned with personal relations and the feeling tones of social situations. Thinking types live mostly in the world of ideas, guided by plans, principles, and “intellectual formulas.” Intuitive types, described in the next section, are guided by signals from their core.
Although one function typically predominates, Jung emphasized the importance of balance and integration among all four functions. This individuation process is innate, and always active, part of normal maturation. But at some point it may also become an intentional goal. We can seek personal growth – better psychological balance, more integrity, grace, and wholeness in our lives.
The Intuition Function
According to Jung, intuition is a spiritual function, “at the centre of the personality.” Here are “the deepest springs of life,” a sense of “divine energy” or “God within.” This core awareness can be cultivated; every person “has something in his soul that can grow.”
Intuition also refers to hunches, insights, and inspirations. Their common feature, Jung said, is a sense of newness. Here’s the “aha” or “lightbulb” experience, ranging in intensity from the glimmer of a hunch, to the flash of creativity, to the illumination of a revelation. But it always involves this spark of intuitive awareness, the nonspecific signal of something new.
Indeed, the sense of newness is the essence of intuition. According to Jung,
“Every ordinary situation in life seems like a locked room which intuition has to open. It is constantly seeking fresh outlets and new possibilities…The intuitive is never to be found in the world of accepted reality-values, but he has a keen nose for anything new and in the making.”
“Intuition is a function which normally you do not use if you live a regular life within four walls and do routine work…People who risk something in an unknown field, who are pioneers of some sort, will use intuition…Whenever you have to deal with strange conditions where you have no established values or established concepts, you will depend on that faculty of intuition.”
And now we know the reticular system is central to the sense of newness –
As described in Essay 1, all vertebrates — from fish to humans — respond selectively to novel stimuli. When something new catches our attention, we feel a spark of awareness, a split-second sense of its newness. This immediate interest in anything new is one of our oldest brain programs, a legacy from the earliest vertebrates, programmed in the reticular core.
Again, the sense of newness is the essence of intuition. And for some people, it’s the guiding force in life. These intuitive types seek new possibilities in the outside world and in their own inner depths. They are the adventurers, explorers, inventors, creative artists, and spiritual seekers. According to Jung, when other psychological functions are also integrated adequately, this type can be charismatic, an inspiration to others —
“[He] can render exceptional service as the initiator or promoter of new enterprises…He can also ‘make’ men. His capacity to inspire courage or to kindle enthusiasm for anything new is unrivaled…He brings his vision to life, he presents it convincingly and with dramatic fire, he embodies it.”
In their religious lives, intuitive types don’t cling to ritual and dogma. Their motivation comes directly from the core, the fluid inner source of all that is new – the soul in continuous rebirth. As Jung said, they “demonstrate the happiness which radiates from the [inner] treasure.” They are “living evidence that this rich and varied world with its overflowing and intoxicating life…also exists within.” They play an important role in society – “had this type not existed, there would have been no prophets in Israel.”
When this type is unbalanced, and other functions are not adequately developed, the personality is peculiar and ineffective. As Jung put it, “all too easily the intuitive may fritter away his life.”
“If only he could stay put, he would reap the fruits of his labors; but always he must be running after a new possibility, quitting his newly planted fields while others gather in the harvest. In the end he goes away empty.”
“But the crank is content with a visionary idea by which he himself is shaped… [This] results in an extraordinary aloofness of the individual from tangible reality…If he is an artist, he reveals strange, far-off things in his art…If not an artist, he is frequently a misunderstood genius, a great man ‘gone wrong,’ a sort of wise simpleton.”
Jung called intuition “the noblest gift of man.” But he emphasized the value of all four functions, and the importance of personality balance for all psychological types.
In summary, intuition comes from the core, from the inner spiritual depths. The reticular system probably plays a major role.
The Sensation Function
“Sensation is therefore a vital function equipped with the strongest vital instinct.”
— Carl Jung
Jung’s sensation function includes external sensation and body awareness, as well as the instinctive drives associated with them. Some writers have referred to it as the “instinct function.” According to Jung, sensation types are ruled by their basic drives, by physical pleasures and pains, and by “purely sensuous reality.”
“This type is the lover of tangible reality, with little inclination for reflection and no desire to dominate…To have sensations, and if possible to enjoy them – that is his constant aim…The great problems of life hang on a good or indifferent dinner…it’s all a question of good taste…His love is unquestionably rooted in the physical attractions of its object.”
For sensation types, the physical world – or “real-world” – is most important. According to Jung,
“No other human type can equal [this] type in realism…His life is an accumulation of actual experiences of concrete objects…Since one is inclined to regard a highly developed reality-sense as a sign of rationality, such people will be esteemed as very rational. But in actual fact this is not the case, since they are…at the mercy of their sensations…[Their] whole aim is concrete enjoyment.”
When other functions are also adequately developed, this type can be a reliable worker, efficient housewife, or good soldier – usually a conventional person, sometimes “conspicuously well-adjusted to reality.” But if the personality is not balanced, he or she may be shallow, shortsighted, even “a crude pleasure-seeker.” Or this type may be overly focused on the body and its sensations, prone to health worries and psychosomatic problems.
The brainstem regulates basic sensory awareness, body functions, and instinctive drives. In sensation types, these programs have a dominant influence on the personality.
The Feeling Function
Jung’s feeling function is concerned with social relationships. He said “people who have a good feeling function are good social mixers; they have a great sense of values.” They are attuned to the emotional atmosphere, to the feeling tones of social situations.
This includes both caring and competitive emotions. Some are more attuned to friendly and affectionate feelings, others more to power and status, but for all feeling types social relations are most important.
“I may feel moved, for instance, to say something is ‘beautiful’ or ‘good,’ not because I find it ‘beautiful’ or ‘good’…but because it is fitting and politic to call it so, since a contrary judgment would upset the general feeling situation. [This] is not by any means a pretense or a lie, it is simply an act of adjustment…This kind of feeling is very largely responsible for the fact that so many people flock to the theatre or to concerts…Fashions, too, owe their whole existence to it…Without it, a harmonious social life would be impossible.”
When well integrated, feeling types can be good parents, friends, and community members, or at least good politicians. They do well in jobs that require social or interpersonal skills. But when not well-balanced, they may have “a tendency to overpower or coerce…a domineering influence.” Or when positive emotions are excessive, and not well integrated, others may sense that lack of sincerity or integrity –
“The personal quality of the feeling, which constitutes its chief charm, disappears…one suspects a pose [or] act…It does not speak to the heart…it gives the impression of being put on, fickle, unreliable.”
The limbic system underlies our social emotions – our feelings about others and our relations with them. In feeling types, it has a dominant role in the personality.
The Thinking Function
Of course, the cerebral cortex underlies our thinking function. In thinking types, cortical processing takes precedence, while feeling, sensation, and intuition play lesser roles in the personality.
These people live mostly in the world of ideas. They focus on solving problems and achieving goals. They are guided by plans and principles, or as Jung put it, “intellectual formulas.”
“By this formula good and evil are measured, and beauty and ugliness determined. Everything that agrees with this formula is right, everything that contradicts it is wrong…So, for their own good, everybody around him must obey it too, for whoever refuses to obey it is wrong…Anything in his own nature that appears to invalidate this formula is a mere imperfection…’Oughts’ and ‘musts’ bulk large in this programme. If the formula is broad enough, this type may play a very useful role in social life…But the more rigid the formula, the more he develops into…a quibbler and a prig, who would like to force himself and others into one mould.”
“There are many people who believe that world problems are settled by thinking. But no truth can be established without all four functions. When you have thought the world you have done one fourth of it; the remaining three-fourths may be against you.”
Scientists, philosophers, educators, executives, and other professionals are mostly thinking types. Their achievements and successes – personal and professional – depend not only on the quality of their thinking, but also on the integrated development of other personality functions.
In summary, Jung’s intuition, sensation, feeling, and thinking correspond to our brains’ reticular, brainstem, limbic, and cortical functions.
In every person, one of these is naturally the strongest and most frequently used function. But mental health and adjustment require at least some development of the other functions as well. Above all else, Jung emphasized the importance of personal growth – a process of increasing psychological balance and personality integration.
“I do not believe that it is humanly possible to differentiate all four functions alike…There will always be a flaw in the crystal…For heaven’s sake do not be perfect, but by all means try to be complete – whatever that means.”
– Carl Jung
“The individuation process [tends toward] ‘wholeness’ or ‘integration’: a condition in which all the different elements of the psyche, both conscious and unconscious, are welded together. The person who achieves this goal…is guided by an integrating factor which is not of his own making.”
– Psychiatrist Anthony Storr
Individuation is Jung’s term for personality balance and integration. It includes normal psychological maturation, but also intentional growth efforts – spiritual practices, psychotherapies, self-help methods, and so on. But the basic force behind them all is the “integrating factor” – the innate drive for balance and wholeness, always active in each of us.
The cerebellum is almost certainly important here. Containing half of the brain’s neurons, and interconnected with all brain regions, its influences are strong. It brings balance and coordination to reticular, brainstem, limbic, and cortical functions. It probably plays a major role in personality integration.
Again, every person naturally prefers one of the four psychological functions. But someone who relies on one or two functions excessively will be unbalanced, more vulnerable to various problems, and won’t experience his or her full potential. Jung maintained that everyone, at some point, feels the need for better psychological balance and integration. And for some people, this becomes a guiding purpose in life.
Individuation begins with increasing self-awareness, and develops into fuller self-understanding. There is an acceptance of, and coming-to-terms with, all aspects of one’s self. As Jung said, this integration “embraces our innermost, last, and incomparable uniqueness.”
In this process neglected functions are recognized, and effort is made to develop them. Balance is sought on all levels – intuition, sensation, feeling, and thinking – as integrative tendencies are cultivated. The personality becomes stronger, more stable and well-rounded. Again, the cerebellum probably plays a major role.
Jung studied the myths, philosophies, and religions of many cultures, and found similar themes of personal growth and integration in all of them. He concluded, as have many others, that this is a basic need, part of human nature. And he maintained that, sooner or later, it becomes a spiritual growth process.
“Individuation, in Jung’s view, is a spiritual journey; and the person embarking on it, although he might not subscribe to any recognized creed, was nonetheless pursuing a religious quest.”
— Psychiatrist Anthony Storr
As self-integration deepens, there’s a pull from within, a stirring in the spiritual depths. The sense of a center emerges, and over time it intensifies. Intuition becomes stronger, as a new awareness grows in the core of the self. It becomes, Jung said, “the centre of gravity of the total personality.”
His descriptions of this “psychic centre” are the same as those proposed for reticular awareness. Here is being, fluid and formless, beyond time and space. Here are “the deepest springs of life,” the “cosmic source of energy,” a sense of “God within.” Here is intuitive awareness, always new, inspiring and illuminating.
As a person becomes more individuated, this psychological center of gravity seems to pull other mental functions to itself. The personality gradually becomes integrated around its spiritual core. Deep spiritual awareness – transcendent Being, a sense of God’s presence – carries over into daily life.
This, according to Jung, is a major theme of most religions. Every person “has something in his soul that can grow.”
“We can hardly escape the feeling that [this] process moves spiral-wise around a centre, gradually getting closer, while the characteristics of the centre grow more and more distinct. Or perhaps we could put it the other way round and say that the centre – itself virtually unknowable – acts like a magnet on [other mental functions] and gradually captures them as in a crystal lattice…Indeed, it seems as if all the personal entanglements and dramatic changes of fortune that make up the intensity of life were nothing but hesitations, timid shrinkings, [and] excuses for not facing the finality of this strange and uncanny process of crystallization. Often one has the impression that the personal psyche is running around this central point like a shy animal, at once fascinated and frightened, always in flight, and yet steadily drawing nearer.”
In individuation, one’s center of balance gradually shifts toward the core.
Does the reticular system generate this core awareness? Does the cerebellum coordinate and integrate other mental functions with it? We have no definite answers, but many reasons to suspect that may be how it works.
Jung also popularized the terms extraversion and introversion. These two psychological attitudes combine with the four psychological functions, making eight basic personality types – extraverted or introverted intuition, sensation, feeling, or thinking types. For their descriptions see any introductory text or website, or Jung’s classic Psychological Types.
You may also be familiar with the Myers-Briggs Type Indicator, a well-known personality profile test based on Jung’s model.
It has long been observed that extraverts seem generally happier than introverts, who may be more inhibited or anxious. Recent research supports that correlation, linking extraversion with more positive emotion and introversion with negative emotion. The brain’s positive and negative emotion systems probably play some role here. However, those correlations are partial, complicated, and not well-understood. Again, the key is individuation – the degree to which extraverted and introverted tendencies are balanced and integrated.
- Myers, Isabel Briggs. Gifts Differing: Understanding Personality Types. Davies-Black Publishing, Palo Alto CA, 1980.
- Jung, Carl. Analytic Psychology: The Tavistock Lectures. Pantheon Books, New York, 1968.
- Jung, Carl. The Portable Jung. Ed J. Campbell. Penguin Books, New York, 1971.
- Storr, Anthony. The Essential Jung. Princeton University Press, Princeton NJ, 1983.