Two roads diverged in a wood, and I –

I took the one less travelled by,

and that has made all the difference.


Robert Frost.


The Philosophical and Scientific Background of Psychostratics: the Stratification Tradition and the Unity Tradition



This article shows that psychostratics is part of the stratification tradition. This tradition is based on the concept of hierarchically ordered layers within psychological functioning (e.g. Freud’s id, ego, and super-ego) and within the brain (e.g. MacLean’s triune brain theory). The stratification tradition stands in contrast with the dominant unity tradition. The contemporary manifestations of this tradition are cognitive psychology (“man as a computer”) and cognitive neuroscience. These approaches focus on cognition (“thinking”) and neocortical functioning, respectively. The description of both traditions makes it clear that the unity tradition addresses only the highest level of psychological and neurological functioning and that the models within the stratification tradition clearly do greater justice to both modes of functioning. Therefore, it is desirable that there should be a shift in dominance towards a stratification framework which will make it possible to integrate the enormous wealth of research and theory in the cognitive sciences. As a starting point for this stratification framework, psychostratics is theoretically best suited, but its present obscurity makes this role quite improbable for the time being.


Introduction: psychostratics, stratification tradition, and unity tradition

Psychostratics starts from a hierarchical psychological stratification. In general terms, these strata or layers are instinctive, affective and cognitive functioning. This psychological stratification leads to dynamic psychological functioning, characterized by complex inhibitions and activations. Within psychological development, psychostratics discerns five possible phases, which differ qualitatively.

These psychological layers are founded on the stratification of the brain in brainstem system, limbic system, and neocortex (MacLean’s triune brain theory (1989)). This brain stratification results from leaps in evolution and is likewise characterized by inhibitions and activations.

In short, psychostratics is characterized by psychological and neurological stratification, dynamics and development. However, psychostratics is not unique in that, the history of philosophy, psychology, and neurology showing several views with one or more of these characteristics. An important example of psychological stratification concerns the work of Freud. And neurological stratification is—in addition to MacLean—an important characteristic of J. H. Jackson’s writings. Both views will be discussed in detail below. These and similar views are named the stratification tradition.

The stratification tradition has a counterpart, which is named the unity tradition. Characteristics of the unity tradition’s views, which are traditionally dominant, are mainly a focus on cognitive or neocortical functioning, limited dynamics due to this focus on one level of functioning and the lack of a developmental perspective, both on an evolutionary and individual level. For the philosophical psychological movement within the unity tradition, this one level usually concerns thought processes. An important exponent of this movement is the contemporary dominant psychology view, cognitive psychology. For the neuropsychological movement within the unity tradition, the focus is mainly on finding connections between cortical and cognitive functioning. Both movements within the unity tradition will be discussed below.


1 The stratification tradition

In philosophy, Nietzsche (see below) is the most important exponent of the stratification tradition. Vroon (1989, p. 43-45; only available in Dutch)[1] mentions Plato (ca. 427-347 BC), Aristotle (384-322 BC), Charles de Bouelles (Bovillus; ca. 1475-1566) and Schopenhauer (1788-1860) as philosophers who divided the human mind (and society) into three hierarchical layers. (These divisions often show a striking resemblance to the triune brain theory of MacLean (see below), the foundation of psychostratics.)

The big bang of the stratification tradition is the theory of evolution since this theory of Charles Darwin (1809-1882) implies the presence of remains of old life forms within new ones. This view is explicitly articulated by the German zoologist and philosopher Ernst Haeckel (1834-1919) in his recapitulation theory, which states that ontogeny (individual development) is a partial repetition of phylogeny (development of the species). Vroon (1989, pp. 45-46) states that “Haeckel’s law (…) has had a great deal of influence on ideas in biology and psychology.” To exemplify this, he mentions the ideas of developmental psychologist Jean Piaget (1896-1980) and of the equally influential Russian psychologist Lev Vygotsky (1896-1934).

This recapitulation idea is also to be found in the work of the English universal philosopher and scientist Herbert Spencer (1820-1903). According to him, the human mind can only be fully understood from a phylogenic perspective. Spencer, who invented the phrase “survival of the fittest,” viewed the growing complexity of neuronal structures during evolution as a stratification process. The evolution concept was also central to his work in the countless other areas that occupied Spencer, who was by far the most popular thinker of his time.

The theory of evolution is also important for the work of the German philosopher Friedrich Nietzsche (1844-1900). His prophecy of the coming Overman (German: Übermensch), for example, can be seen as an evolutionary consequence. The stratification tradition’s dynamic aspect is visible in Nietzsche’s antithesis of the Apollonian (rational thinking, harmony, and beauty) and the Dionysian (irrationality and chaos; emotions and instincts). (This antithesis is also a part of psychostratics, though in a different form.) An important source of the dynamic character of Nietzsche’s philosophy is his liking for the pre-Socratic philosopher Heraclitus (ca 540-480 BC), whose emphasis on genesis and dynamics is known from the famous phrase Panta Rhei (everything flows), which is attributed to him.

The English physician and neurophysiologist Thomas Laycock (1812-1876), one of the founders of physiological psychology, is also an important exponent of the stratification tradition. Laycock was the first to formulate the concept of reflex action within the brain. He distinguished between a self-conscious mind and an unconscious intelligence where reflexes were seeded. Laycock classified insanity into three types: orectic insanity, thymic insanity, and phrenic insanity. Each type of insanity was associated with a disorder in encephalic centers that controlled instincts, feelings, or reason. Laycock explained moral insanity and mania through the concept of “reversed evolution,” a concept that was later furthered by his student John Hughlings Jackson (see below). Jackson also recast Laycock’s concept of the continuity of nervous systems in animals through evolutionary proof.

In addition to Laycock’s work, the British neurologist John Hughlings Jackson (1835-1911) was influenced by the views of Spencer. The similarities between Spencer’s evolutionary neurological conceptions and his own clinical observations were the reason for Jackson to distinguish three brain levels, with the higher levels inhibiting the lower ones. Reduced or absent inhibition, for example as a result of a lesion of the higher level, causes, within a lower level, either phenomena of deficiency (“negative” symptoms, e.g. paralysis) or disinhibition (“positive” symptoms, e.g. reflex or spastic behavior). These phenomena of deficiency involve a return to ancient evolutionary functioning or dissolution, a concept that Jackson adopted from Spencer. This theory, which in my opinion makes Jackson the father of the layered brain view, offers the possibility of gaining insight into the evolutionary development of the brain through neurological and psychiatric symptoms. Since then, the view of a hierarchically organized nervous system has been validated for a large variety of neuronal systems by neuroscientists. In this regard, Kolb and Whishaw (1990, p. 176) refer to Henry Head (1861-1940) and Alexander Luria (1902-1977).

At about the same time, the German-Austrian psychiatrist, neuropathologist and anatomist Theodor Hermann Meynert (1833-1892) was the director of the psychiatric clinic associated with the University of Vienna. In regards to mental illness, Meynert conceptualized that a conflict existed between the cerebral cortex and the subcortical regions as the primary cause for abnormal function of cerebral components. Meynert’s most famous student is Freud (see below), who has worked at his psychiatric clinic. (Incidentally, Meynert later distanced himself from Freud because of the latter’s “unscientific” involvement with hypnosis and extension of hysteria to the male – after all, ‘hysteria’ originates from the Greek word for uterus. Near to his death, however, Meynert reconciled with Freud.)

So, profound influences on the work of Sigmund Freud (1856-1939) are ideas of Laycock, Meynert, and especially Jackson. In his “Project for a Scientific Psychology” from 1895 (Freud, 1954), he tried to base his psychology on Jacksonian neurology. When this proved impossible, Freud transformed his neurological view into psychological ones. For example, the hierarchically ordered brain shows affinity with the division into Conscious, Preconscious, and Unconscious, with in both cases inhibition of the lower levels by the higher ones, and return to an earlier evolutionary stage is related to the regression concept. However, Freud remained convinced of the importance of a biological foundation for psychoanalysis. “The theoretical structure of psychoanalysis that we have created is in truth a superstructure, which will one day have to be set upon its organic foundation. But we are still ignorant of this” (Freud, 1973, p. 436). Apart from Jackson’s theory (and ideas of Laycock and Meynert), Nietzsche’s philosophies seem to be an important source for Freud’s work. (Freud himself denies this, but research on this subject gives little reason to doubt it, e.g. Chapman et al. (1995).)

A Jacksonian hierarchically organized brain is even more present in the triune brain theory formulated by Paul MacLean (1913-2007). This theory (1989) distinguishes within the human brain between a “reptilian brain” (brainstem and similar structures; instincts), a “mammalian brain” (limbic system; affects) and a “human brain” (neocortex; thinking). These brain layers differ in age, structure, and functioning.

An attempt to combine Freud’s work with the concept of a layered and hierarchically organized brain is neuropsychoanalysis. The founders of this interdisciplinary approach are neuroscientist Jaak Panksepp (1943) and psychoanalyst Mark Solms (1961). A brief discussion of neuropsychoanalysis can be found in their joint article (2012). (The neuropsychoanalytical model discussed briefly in it shows a striking similarity with the psychostratic model.) An important goal of neuropsychoanalysis is to improve treatments within mental health care.

Finally, it should be noted that inner stratification and dynamics are characteristic of many highly appreciated works of art. Examples of this are the inner conflict of Shakespeare’s Hamlet and Dostoevsky’s Raskolnikov (Crime and Punishment). A literary work that explicitly addresses the different forces within the mind is “The strange case of Dr. Jekyll and Mr. Hyde” (1886) by R. L. Stevenson (1850-1894). (It is revealing that Freud was very knowledgeable of the world literature of his time.) These instances of dynamic stratification from literature can easily be extended to the other arts (Beethoven, Picasso.) (Psychoanalytic views are an important source of this type of art. Mainly through this use (and that within psychiatry), psychoanalytic views, which have been rejected by academic psychology, have ironically become an integral part of our culture—something no other psychology has ever accomplished.)


2 The unity tradition

The vital importance of the theory of evolution within the stratification tradition has its counterpart in the more or less unconscious influence of Christianity and its inherent mind-body dualism within the unity tradition. This religion sees man as secluded from the animal and endowed with an eternal soul and reason by God. This gap between man and animal was further widened by the mind-body dualism of the French philosopher René Descartes (1596-1650). According to this view, the body of man and animal is an ingenious mechanism, whereas only man has an immaterial and eternal soul. So all the characteristics of the unity tradition are strongly present here. Focusing on the functioning of one level and limited dynamics concerns rational thinking (reason), and the lack of a developmental perspective, evolutionary or otherwise, is inherent to the concept of an eternal soul.

(It requires some puzzling, but after that psychological stratification can also be found in Christianity. At the core of Christianity lies the good-evil dichotomy, the first being connected with God, the pure soul, and rationality; and evil with the devil, corporality (sex!), and instinctual and affective behavior. However, from a psychostratic (and psychoanalytic!) perspective, the devil and his whisperings can be interpreted as projections of instinctual and affective functioning.)

Mind-body dualism is crucial for the unity tradition’s division into a philosophical and psychological movement (2.1) and a neurological movement (2.2). Within the stratification tradition, on the other hand, both movements are much more intertwined owing to their common evolutionary background.

2.1 Philosophical and psychological movement As shown above, Christianity’s body-mind dualism is of great importance for the unity tradition. This dualism strongly coincides with Platonic and Neoplatonic concepts, specifically with his theory of Forms – so Plato belongs to both traditions! In particular, Christianity’s high appreciation of the soul, heaven, and rationality strongly correspond with the great importance given to eternal, absolute and unchangeable Forms, the Good as highest of these Forms, and rationality as the way towards the Forms. There is also the Christian view that Platonic forms are the thoughts of God. The church’s disdain for the animal side in man and material reality corresponds to the Platonic views that the appearances are imperfect reflections of the Forms and that the spiritual is good and the material is bad (Christoplatonism). Finally, “the domination within psychology of the Platonic Idea of the universal and unchangeable man is caused by its following of the natural sciences, in particular physics, throughout its history” (Peters, 1994, p. 24; not available in English).

Apart from Plato and Descartes, the unity tradition has many exponents in philosophy. “The prevailing opinion in philosophy has been that psychological processes are related in a meaningful way in man. In other words: to the extent that a typical human mind exists, it is seen as a unity and a unique characteristic” (Vroon, 1989, p. 65; not available in English). “In the thought of many philosophers, the strangeness and indescribability of emotions and instincts are conveniently converted into the statement that they are not the core of existence. That point of view is one-sided and reprehensible (ibid., p 164).”

An important source of the philosophical and psychological movement within the unity tradition is associationism. This philosophical psychology concerns the emergence and laws of the ideas of consciousness (“thinking units”). Associationist philosophers thought the succession of these ideas was the result of association laws (in particular those of similarity, simultaneity, and contrast). The concept of association can already be found in the works of Plato (ca 427-347 BC) and Aristotle (384-322 BC), where it relates to memory. The father of postclassical associationism is the English philosopher and physician John Locke (1632-1704). According to Locke, the mind is empty at birth, a tabula rasa; knowledge is only possible by associating experiences, which result from sensory perception. This is not only a view on the human mind, but also an epistemology. According to this empiricism, the scientific method simply comprises an ascent from the phenomena into more abstract concepts. This is called induction. After Locke, a whole series of mainly British philosophers contributed to associationism, and in many cases to empiricism as well.

At the start of the 20th century, American psychologists wanted to present themselves as real, empirical scientists, just as their shining example, the natural scientists. However, associationist views are completely unsuited for this, since the contents of consciousness cannot be observed objectively. Consequently, induction is impossible as well. Furthermore, the practical relevance of these views proved limited and therefore American psychologist John Broadus Watson (1878-1958) introduced behaviorism in 1913. This psychology viewpoint focuses on observable human and animal behavior. More specifically, this concerns the connections between variations in environmental stimuli and the resulting responses. The goal of behaviorism is to predict and control human behavior. It was further specified by the classical conditioning theory of the Russian physiologist Ivan Petrovich Pavlov (1849-1936). This theory shows how a connection between stimulus and reflex is established. In 1945, Burrhus Frederic Skinner (1904-1990) presented his conception of behaviorism. Skinner was mainly involved in experiments in the field of operant conditioning (the behavioral consequences of rewards and punishments). With the rise of behaviorism, psychology’s focus has shifted from Europe to America.

The American war efforts during the Second World War brought the need for psychological knowledge in fields such as information processing, attention, and decision-making. Since behaviorism could not provide this knowledge, psychologists made use of the information theory of the American mathematician and electrical engineer Claude Elwood Shannon (1916-2001), in which man is conceived as an information channel, such as a telephone. The English experimental psychologist Donald E. Broadbent 1926-1993), whose filter theory was connected with information theory, brought consciousness back into psychology.

In the 1950s, two developments in particular led to the rapid rise of cognitive psychology. These were the criticism the American linguist Avram Noam Chomsky (1928) leveled at behaviorism, and more generally at empiricism, on the one hand, and the arrival of the computer, on the other hand. Developments in the field of computers led to the view of man as an information processing system. This idea was disseminated in particular by the American scientists Herbert Alexander Simon (1916-2001) and Allen Newell (1927-1992), who were mainly concerned with artificial intelligence. Cognitive psychology, which took over behaviorism’s dominant position, concerns mental processes such as attention, memory, perception, language and problem-solving.

(However, cognitive psychology completely neglects instinctual functioning and trivializes the importance of emotional functioning, or it stretches the concept of cognition to such an extent that both ways of functioning disappear in boring uniformity. An example is the following. Psychologist Zajonc (1980, 1984) advocates an empirically based distinction between psychological systems that process cognitions and emotions, respectively.  So, he proposes a layered model. Lazarus (1982, 1984) mainly responses by expanding the concept of cognition to such an extent that a separate system for the processing of emotions becomes redundant. This is the more striking because of Lazarus’ background in psychoanalysis, i.e. one of the most important exponents of the stratification tradition.)

The concepts and theories of cognitive psychology are applied in many fields: psychopathology, social psychology, developmental psychology, educational psychology, and personality theory.

A major criticism of cognitive psychology is the limitlessness of its model of man as an information processing system, leading to “an enormous proliferation of research data and theories that are hardly connected” (Boon, 1982, p. 131; not available in English).

On closer consideration, all of the psychology views of the unity tradition turn out to be variations on one model: S -> O -> R. It concerns an organism (human or animal; O) with stimuli (S) going in and responses (R) going out. With Locke, the S concerns sensory perception and the O stands for the association of ideas within consciousness. Behaviorism renounces introspection of consciousness and instead focuses entirely on the S and R, since these can be observed and experimented on. (However, the difference between associationism and behaviorism is not as large as it might seem, since connections are central to both of them. With associationism, ideas are linked within consciousness. Behaviorism focuses on connections between either stimuli and reflexes (classical conditioning) or behavior and its consequences (operant conditioning).) The pragmatic cognitive psychologists place the O (cognitions) at the center again, just as in associationism, but this time in an empirical and scientific way. But its model of computer man is limitless to such an extent that its adherents drown in a sea of research data and get lost in a forest of theories.

2.2 Neurological movement An important early exponent of the unity tradition’s neurological movement is phrenology, whose founder is the German physician Franz Joseph Gall (1758-1828). This abandoned theory presumes a connection between the shape of the skull and character. In common parlance, phrenology lives on in phrases such as “highbrow”, “lowbrow” and “well rounded.”

The next shoot on the present development branch are localization theories. The basic assumption of these theories is that specific brain areas are connected with certain forms of psychological functioning. Here, Broca and Wernicke should be mentioned. The French physician, anatomist, and anthropologist Paul Pierre Broca (1824-1880) discovered that damage to a specific area of the left frontal lobe (Broca’s area) could cause trouble with talking and understanding grammar (motor aphasia). Carl Wernicke (1848-1905), a German anatomist, neurologist, and psychiatrist, found that disorders or lesions to a part of the temporal lobe (Wernicke’s area) could lead to dyslexia and sensory aphasia (fluent but meaningless speech).

Halfway through the 1970s, the unity tradition’s neurological and psychological movement converged in cognitive neuroscience. This integrative approach particularly focuses on locating the higher cognitive functions within the neocortex and the underlying neural mechanisms. For this, mainly research of patients with brain damage is important. An example is the research conducted by one of the most important cognitive neuroscientists, the American neuropsychologist Michael S. Gazzaniga (1939), who studied the functions of the left and right hemispheres in patients whose corpus callosum (the connection between the hemispheres) had been cut. However, cognitive neuroscience still has a whole range of other research methods, such as neuroimaging techniques. Through the use of techniques such as fMRI, the American psychologist and cognitive neuroscientist Stephen Michael Kosslyn (1948) discovered several neocortical networks for spatial imagining. The research seemed to indicate that the left hemisphere’s images are more abstract, while these of the brain’s right half are more specific. The present “prevailing theory that still influences the way current neuroimaging techniques interpret brain function can be traced back to classical localizational theories (…)” (Wiest, 2012, p. 1).

A neuroscientist who, apart from cognitions, mainly studies emotions is the influential Portuguese American researcher and clinician Antonio Damasio (1944). He notably researches neuronal systems that are at the base of emotions, decision-making (somatic marker hypothesis), memory, language, and self-awareness. According to Damasio, emotions play a decisive role in higher cognitive processes. This view runs counter to the dominant psychological, neuroscientific and philosophical outlooks of the unity tradition. Moreover, Damasio’s view on the origins of cognitive psychology shows a striking similarity with the current one. “The Cartesian idea of ​​a bodiless mind … could have been the source for the metaphor of the mind as a software program” (Damasio (1995), p. 271).[2] However, Damasio seems to make no hierarchical distinction within psychological functioning (emotions and cognitions) or within neurological functioning (e.g. brainstem, amygdala, and neocortical structures). So he stretches the unity tradition’s framework to its limits but stays inside of it.


3 Conclusion: integration of unity and stratification tradition in the stratification framework

It is clear from the foregoing that the unity tradition’s neurological and psychological movement represents only half the story of brain and mind, since they confine themselves to higher brain and cognitive functioning. In these areas, however, this dominant tradition has produced an enormous wealth of research data and theory.

In contrast, the stratification tradition does justice to neurological and psychological functioning in its entirety. However, the most important contemporary view of this tradition, neuropsychoanalysis, has a number of problematic aspects. (1) The connection between the many Freudian concepts is often unclear. This complicates linking these concepts to neurological data. (2) Freud’s work is seen as unscientific by the dominant cognitive sciences, mainly because it is not based on empirical scientific research. (3) Neuropsychoanalysis can never dethrone cognitive sciences because of its marginality and the lack of overlap between them.

Consequently, the only possibility to arrive at a science that does justice to the whole of neurological and psychological functioning is a framework from the stratification tradition that accommodates cognitive sciences as effortlessly as possible. This broad stratification framework involves the following connected points. The first three points refer to the framework’s scientific core and run from more to less basal. The second one offers a source for the framework outside science. The last point concerns the scientific method.

  1. The foundation of the stratification framework is the theory of evolution. Ultimately, man is a biological being, whose behavior has been grounded on self-preservation and preservation of the species. (But it is certainly not the case that all behavior can be traced back to both forms of preservation.)
  2. There are leaps in evolution. According to the neurological stratification view, this has resulted in a hierarchical stratification of the brain, involving a complex of inhibitions and excitations.
  3. The brain’s stratification is connected with the stratification of psychological functioning. This connection between neurophysiological and psychological functioning has to be further determined.
  4. However, experiences, data, and views outside the neuropsychological and psychological sciences that reflect dynamic and layered psychological functioning are also valuable for the stratification framework. These matters mainly concern works of art, but myths and religion, history, and anthropology can also be of importance.
  5. The integration of different neurological, psychological, and other views within the stratification framework conflicts with the cognitive sciences’ view of science. This view concerns strict empiricism, meaning induction from phenomena to theory. But the resulting number of references is not a measure for its scientific value. For the transition to the stratification framework to succeed, this “empirical fixation” will largely have to give way to creating a falsifiable and internal consistent stratification framework that can accommodate existing theories and research data. This is particularly important at the start of the transition. After establishing this framework, its further development will have to consist of two intertwined processes. These processes concern empirically testing hypotheses from the stratification framework and adapting the framework as a result of this empirical research.

How could the transition to the stratification framework take place? Possibly, cognitive scientists may come to see that they only occupy themselves with the highest layer of brain and mind and take the obvious step. Despite the presence of a scientist as Damasio within the unity tradition, it is more likely that this transition to the stratification framework will be made by scientists within the stratification tradition. For example, neuropsychoanalytical scholars might try to integrate cognitive scientific opinions and theories within their framework. However, the most probable and desirable point of departure for the transition to the stratification framework would be the psychostratic model, because this developmental model integrates most important theories and views mentioned above: the theory of evolution, Nietzschean thought, psychoanalysis, triune brain theory, conceptions of art, behaviorism and cognitive psychology. Moreover, psychostratics offers psychological operating mechanisms in detail and has a high degree of internal consistency. A practical disadvantage of psychostratics, of course, is its current obscurity.

So, there’s a road to follow, long and hard.
But what’s a greater reward
than a clear look in the mind’s mirror?


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[1] Originally Dutch; the author’s own translation. This is the case for all texts in this paper that are only available in Dutch.

[2] Originally Dutch; the author’s own translation.