Table 1: TCM and SCM philosophical foundations.

Traditional Chinese medicines (TCM)Sasang constitutional medicine (SCM)

Neo-Confucian Views
BackgroundTaoist Views
Choi et al. [6]: The foundation of most traditional eastern Asian philosophies and sciences originated from the concepts introduced in I Ching (The Book of Changes)
Song [7]: TCM adapted and expanded upon the Taoist philosophy of the universe reconceptualizing how the macrocosmic universe manifests within the microcosmic sphere of human physiology
Chae et al. [8]: Traditional Chinese Medicine is based on Taoism and explains the universe through the Yin-Yang theory and the Five-Phase theory
Kim et al. [4]: Lee Jema, the founder of Sasang philosophy, was a follower of the RealistSchoolof Neo-Confucianism and was influenced by his teacher Dasan Jung Yakyong (1762–1836). Sasang philosophy initially draws upon ideas about the human body from the Internal Classics Lingshu including the theory of Yin and Yang and the theory of the twenty-five body types. The philosophy incorporated ideas concerning the mind from Mencius, who taught about four vices: ignobility, frivolity, avarice, and timidity
Song [5]: According to Sasang philosophy, one strives “to value good and to scorn evil,” and “to understand others and to rectify oneself,” through a righteous steadfast mind to be in control of one’s mind. This philosophy is rooted in Mencius’s concepts of the “Unmoving Mind” and “Collecting the Mind.” As a result, the philosophy of “Rectification of the Self through Controlling the Mind,” led to the Sasang therapeutic approach of “Controlling the Mind to Heal the Body”. Therefore, according to Sasang philosophy, one will be able to control one’s illness and rectify oneself when one returns to and maintains the state of a righteous mind
Song [7]: The main philosophical basis of Sasang philosophy is human nature and interpersonal relationships rooted in Confucian foundations within a completely human-centered paradigm
Park and Song [9]: Korean Sasang medicine is based on Neo-Confucian philosophy and the Dongeuibogam (Treasured Mirror of Eastern Medicine), a Korean medical text
Yeo [10]: Sasang typology, which describes nature through a quaternary system, is based on a combination of Neo-Confucianism and the medical traditions of Korea
Song [11]: The TCM constitutional approach was first mentioned in Chapter 72 of LingShu of the Inner Classics as five body types. In 1894, Lee Jema presented SCM, which adapted or refuted ideas from the classics. For example, Lee Jema stated among the five body types, Greater Yang type, Lesser Yang type, Greater Yin type, Lesser Yin type, and Yin-Yang balanced type, described in the Inner Classics, that the Yin-Yang balanced type, a perfect human type, did not exist. Moreover, he claimed that this classification was impractical from a clinical viewpoint
Kim et al. [12], Kim and Pham [13], and Kim et al. [14]: The mind-body interrelationship reflects deeply ingrained Neo-Confucian ideologies such as its concepts of morality, the Four Virtues: Benevolence, Rightness, Propriety, and Wisdom

AssumptionQi as the Basic Substance of the Universe
Lee [15]: Based on the macro- and microcosmology, the human being is defined as a microcosm within the macrocosm, and this concept overrides the specificity and individuality of each human being
Giovanni [16]: Qi is present in all objects and provides the metaphysical and physical material that comprises humans. Therefore, regardless of its extrinsic form, the intrinsic qi is universal and the same
Individual Variability
Lee [15]: Sasang philosophy describes the human being as a progressive manifestation of the four constitutional differentiations of the lesser and greater organ structure scheme that is formed through the expression of the innate Seong-Jeong (Innate Nature and Emotional Disposition) of Sorrow, Anger, Joy, and Pleasure
Chae et al. [8]: It also explains individual differences in patterns of behavioral tendencies and physical characteristics based on particular biological and psychological traits
Song et al. [17]: The external causes of illness (wind, cold, summer heat, dampness, dryness, and heat), the internal causes of illness (food, fatigue, and other miscellaneous causes), and the mental influences(sorrow, anger, joy, and pleasure) do not affect all individuals to the same degree. Different individuals with different constitutional makeups exhibit varying levels of vulnerability and responsiveness
Classification of Individuals
Leem and Park [18]: (SCM) classifies people into four constitutional types primarily based on an individual’s psychological and physical traits. Susceptibility to diseases and response to drugs vary upon (an) individual’s constitution. The constitutional type is very much the same as the genetic polymorphism which is determined at birth and remained unchanged throughout one’s life

NatureHumans
FocusChae et al. [8]: Traditional Chinese Medicine places importance on harmony between humanity and nature
Giovanni [16]: The universe originates from qi, and the formation, extinction, variation, and movement of qi are governed by a uniform law and order. Because the humans are microcosms originating from the same qi, they have the same integrity and identity as the macrocosm and are governed by the same laws as the universe
Choi [19]: Human matters influence the physiological and pathological conditions. In Dongeuisoosebowon (A Discourse on the Origin of Eastern Medicine), (Lee Jema) states, “Most doctors in the past did not understand that diseases arise from disruptions of the mind such as love, hate, desire, joy, anger, sadness and pleasure,” and that the Innate Nature (Seong) and the emotional disposition (Jeong) that arise from involvement in human affairs are the primary causes of illness
Chae et al. [8]: Sasang typology emphasizes harmony in (one’s) social life and developing one’s character

Sasang Theory
Ji [20]: The TCM Pathway, Taiji Yin-Yang Sasang, is reinterpreted in the Sasang Philosophy as Mind Mind-Body Activity-Mind-Body-Matter
Kim [21]: The Sasang (four principles) are derived from the I Ching, which describes the development of Taiji into Yin-Yang into Sasang
Perspective
Choi and Park [22]: The “theory of uniformity external factors and internal factor” states that the source of the externally manifested factor originates from an individual’s internal mind, specifically the Seong-Jeong. In SCM morphology-based therapeutics, deviation of the Seong-Jeong is the foremost important factor in morphological expression
Main theoryLaw of the Yin-Yang and the Five Phase
Giovanni [16]: Changes in the human body can also be observed and predicted within the Yin-Yang and the Five-Phase theories
Kim and Song [23]: In Huangdi’s Internal Classics, the Five-Phase theory, external morphology and symptoms are classified according to their corresponding five visceral zang organs
Kim and Song [23]: According to SCM four-axis schema (Sasang) of Activity-Mind-Body-Matter theory (AMBM), external morphology and symptoms are classified by characteristics of the relative “largeness” and “smallness” of the internal organ schema, Seong-Jeong, and Disruptive Desires, or greed. The morphology in Sasang constitutional medicine can be said to have typological implications
Song [24]: Lee Jema derived his system based on Confucian concepts of Seong-Myeong (pertaining to the human being as a predetermined and preordained existence, inherited congenital aspects) and Ji-Haeng (pertaining to the human beings as a self-governing and self-preserving existence). … he proposed a method of self-cultivation in speech and conduct, setting a novel code of conduct also suggested constitutionally differentiated ways in Ji-Haeng based on the constitutional differentiation according to Sasang constitutional medicine, proffering a new paradigm in medical therapeutics. When deviating from the ethical and moral lifestyle because of temptation, one can fall prey to disease. If one's thoughts and actions are improper and indolent, this can trigger pathological conditions
Lim et al. [25]: The Activity-Mind-Body-Matter Sasang theory is the framework which explains Lee Jema’s perception of the human being. The human being is initially divided into a Mind-Body dichotomy. The Seong (Innate Mind) reflects in the Mind and is associated with knowledge, and Hyeong (Expressed Form) is the expression of speech and conduct within and is associated with action. The internal self Seong is divided into mind and body: everything outside of self (not self); Hyeong is divided into activity and matter, forming an Activity-Mind-Body-Matter quaternary
Lee [26] and Lee et al. [27]: Humans are defined as either self or not of self, literally “outside of self.” Self is further specified as Mind and Body; outside of self is Activity and Matter
Kang and Park [28]: One elementary paradigm of Sasang theory is the duality of form and function. The Heaven/Human-Seong/Myeong grouping of the quaternary is found in the structural scheme of the Sasang quaternary, whereas the Heaven/Seong-Human/Myeong grouping of the quaternary is found in the functional scheme of the Sasang quaternary. This paradigm can be applied to interpreting social life as well as an individual. If the structural scheme forms the basic elements in life, the functional scheme is involved in making life distinctly human

Health and longevityConformity to Nature
Jeong et al. [29]: The classical texts emphasize that the most important aspect of self-restraint is to be in control of one’s mind. Such ideas are found in the Dongeuibogam and were practiced as part of the Taoist tradition
Jeong et al. [29]: In the Taoist tradition, wu wei (letting it be) is essential to maintain self-restraint. The Dongeuibogam states that self-restraint is of utmost importance. The factors that influence self-restraint are age, original qi, congenital state of health before birth and environmental factors after birth. (preheavenly and postheavenly qi)
Han and Li [30]: A pathological condition is essentially a state of disharmony with nature; therefore, the purpose of therapy is to restore harmony with nature
Self-Cultivation
Choi [19]: Lee Jema explains that the penchant for indulgence in the Four Vices (drinking, sensual pleasure, money, and power) can be a life threatening. (Lee Jema) expounds that “the Four Virtues of attentiveness, simplicity, knowledge-ability, and vigilance leads to longevity,” because “he who values attentiveness can avoid indulgent drinking, he who values simplicity can avoid temptation for sensual pleasures, he who values knowledge-ability can avoid hoarding of wealth, and he who values vigilance can avoid striving for power”
Jeong et al. [29]: One should act cautiously after contemplative introspection. Lee Jema believed the cardinal rule when interacting with others to behave in a manner which improves and harmonizes everyone’s life
Jeong et al. [29]: Life expectancy is greatly determined by lesser hypoactive organ’s functional capacity. In addition to life expectancy, a person’s the lesser organ’s functional capacity determines the quality of health as well as severity of illness. A person is born with a defined amount of preheavenly qi. During childhood, adolescence, and early adulthood, one is able to sufficiently live with no qualms with postheavenly qi from food and stores of excess qi in the four visceral organs. After one’s body weakens in middle life and old age, then, one is unable to maintain sufficient energy from postheavenly qi. Then one must draw upon previously stored excess qi to balance the difference. As one ages, he is unable to continuously or indefinitely draw upon or efficient use stored qi. Therefore, to regulate and increase the quality of qi, one must control his mind (침심). The better one is able to control their mind, the more efficient his use of qi and quality of life will be. This philosophy is based upon the idea that the mind and body are one unit and the mind can control the functions and quality of the body
Yoo et al. [31]: Exercise self-restraint in order to extend one’s lifespan. Cultivate self-restraint by controlling one’s mind or understanding of others. A person’s lifespan is a measure of how well that person cultivated self-restraint. Sorrow, anger, joy, and pleasure emerge from social relationships. If one is able to successfully navigate social relationships and use self-restraint, then one will be able to foster a longer lifespan. If one cannot successfully navigate relationships of society, then one will harm the qi of the four visceral organs. When this happens, one’s life expectancy decreases. Therefore, to extend one’s life expectancy, it is essential to preserve one’s prone lesser organ through controlling one’s mind and understanding others
Song [32]: By avoiding harm to the lesser hypoactive organ and virtuously controlling one’s mind and interactions with others to build postheavenly qi, one is able to compensate for the shortcomings of the lesser hypoactive organ and extend one’s life expectancy. One’s life expectancy can fluctuate based on adjustments to one’s self-restraint. Therefore, based on a person’s ability to manage himself, he will prevent potential weaknesses and illnesses. As a mind-centered approach committed to amplifying wellness of the mind, through treating the mind, a physician is able to indirectly treat the organs and extend the patient’s life