Karma in Jainism

Karma is the metaphysical category that accounts for the relationship of transcendental cause and effect in the world due to one’s actions. Karma is understood in Jainism to be a complexity of material particles that bond to the soul through the activities of mind, body, and speech that either extend or shorten the duration of the soul’s embodied, physical existence.

Introduction

It is said that the doctrine of karma is the central dogma within Indic philosophies for explaining the relationship of cause and effect within the world [4]. Further, it is also said that karma is responsible for the many and varied differences in the status and successes of different life forms [3]. In lieu of a principal such as divine providence wherein the world is governed by the sovereign will of a creator, karma is a-theological in character and is understood to be those actions, words, and deeds, which produce invisible and transcendental effects (vasana) that are left behind and impact the life cycles of ensouled beings in the world. Thus, one can think of karma as understood within the Jain tradition to be a metaphysical-physical principle that pertains to action within the moral domain. Karma can be understood as a type of physics within Jain philosophy: karma is responsible for the many differences that one sees between individuals anywhere from body and gender to class and social status. The idea of the transmigration of the soul ensures that karma accumulated in this life will have an effect on one’s birth and life in the next. Therefore, through the ethic of ahimsa (see Ahimsa), Jainism understands the telos of life to be centered around shedding one’s karma in order to attain liberation of the soul (see Moksha) from embodied existence.

What is unique about the Jain understanding of the doctrine of karma relative to both the Vedic and Buddhist traditions is its intrinsically material character: subtle matter particles called pudgala permeate the entire cosmos (loka) which become karma when bonded to the soul through the media of the psychic activities (bhava karma) of mind, speech, and body [9]. This “materialization” of karma is achieved through the bonding of these pudgala in the space points of the soul, thus creating a physical karmic field covering the soul. One will hear Jains describe this notion of karmic bonding with the example of how dust is attracted and bonded to an oiled cloth. The state of one’s soul (passions, aversions, attachments, etc.) affects the bonding of such karmas, and so though the type of karmic influx is set and determined based on actions regardless of who is committing those actions, the level of spiritual development of an individual will determine the duration of bonding. If one’s soul is sufficiently advanced along the fourteen stages of spiritual development (gunasthanas), the karmas, while indeed attracted to the soul due to the soul’s physical and psychic activity, will nevertheless be unable to bond to the soul and fall away like dust off a well-polished surface. These karmic particles when bonded to the soul are called dravya karma and have descriptors such as taste, touch, and color. As the empirical soul continues throughout its life, therefore, it incurs an influx of these dravya karmas that must run their course depending on the spiritual development of the individual before they fall away. As such, Jainism has a strict understanding of karmic accounting wherein the “balance sheet” of one’s karmic debt must be paid in full before liberation of the soul is possible.

Jainism’s unique, material understanding of karma is comprehensive and has been systematically developed throughout the centuries finding its strongest formulation in the Tattvartha Sutra by Umaswati (see Tattvārtha-Sūtra). Additional textual sources for the doctrine of karma can be found in the Satkhandagama, Pañcastikayasara, Karmagranthas, and Gomateshwara. However, the most comprehensive analysis of Jain karma doctrine in the modern period is the 1942 work by Helmuth von Glasenapp, The Doctrine of Karman in Jain Philosophy.

Karma, Cosmology, and Nonviolence (Ahimsa)

Given Jain philosophy’s nontheistic metaphysics and cyclic cosmology, there is an intrinsic relationship between the Jain understanding of the nature of the cosmos and the Karmic laws that govern its functioning and development. The universal system disclosed in the Tattvarthasutra is called the loka [1]. The universe is singular; it is uncreated; it has neither beginning nor end; it is finite in spatial extension and takes the shape of a squared outline of a human body; it consists of the infinite repetition of six time cycles; and it has existed for eternity and will continue to do so. Outside the loka is the aloka: the void. In contradistinction to the Abrahamic traditions where God and the afterlife stand objectively distinct and “outside” of the created space-time universe, Jain cosmology understands there to be nothing beyond the limits of the loka. Jainism posits the liberated state of the soul to reside for eternity in the siddhaloka – the uppermost realm of the universe. Thus, human beings, subhuman beings (animals, plants), heavenly beings (angel analog), hellish beings (demons), and moksha (liberation of the pure soul) exist within a single unified field of existence (loka) governed by karmic physics.

The physics of karma as a law of cause and effect underlies the physical laws of nature and psychological states within the temporal portion of the loka called jambudweep, which is the common physical universe inhabited by all living beings. According to Narendra Bhandari’s analysis of Jain karmic philosophy, “the physical processes occurring in the universe follow the law of causality ‘Nothing happens without a cause and every action has an effect’. This law of causality, applicable to sentient beings, in the spiritual domain is Karmavad of Jainism” [1]. Since Jainism believes anything with a life force is an ensouled being (see Jiva), all living beings are considered sentient in Jainism, and so all are affected by karmic physics. Moreover, because of this relationship between karma and matter, one cannot make a distinction between physics and metaphysics within the Jain tradition for both are conflated in the understanding of the relationship between the ultimate state of the pure soul and its transmigratory journey via reincarnation as an embodied soul governed by karma. Because soul (jiva) is the fundamental and irreducible descriptor of the ultimately real in the Jain metaphysical system, all physical and psychic causes and effects revolve around how these forces relate to each soul’s transmigratory journey through the cycle of rebirth and (hopefully) eventual liberation from the physical world. Contrary to other Indic philosophical systems, Jains do not deny physical reality as illusion but instead stress its intimate relationship with karma in order to explain the moral forces that govern the universe. Karma is therefore a means of explaining how the embodied soul is responsible for its action in the universe and how the consequences of those actions are born out in the embodied forms of the soul in this life and the next.

A helpful way for Western audiences to understand the doctrine of karma in Jainism is to think of it as functionally analogous to the doctrine of divine providence in the Abrahamic traditions. Both are supernatural metaphysical postulates that account for the goings-on of the physical world formulated in a prescientific age. But where it is God’s providential will that is responsible for why things behave the way they do in the Abrahamic traditions, the Jain understanding of karma inverts this understanding and holds the individual fundamentally responsible for the causes and effects born out of his or her action within the material world. It is therefore only the actions of the empirical soul that lead to the influx of karmas that maintain one’s existence in the transmigratory cycle of rebirth in physical form. It is the responsibility of the empirical soul to live out the effects of those karmas for the duration of the soul’s embodied life as well as in possible future lives depending on the extent of accumulated karma at death. Karmas are therefore alien to the soul’s pure state, and so the ultimate teleological aim in Jainism is for the embodied, empirical soul, to learn the path of liberation by following the teachings of the Jinna (enlightened ones) (see Jina) in order to shed its karma and attain liberation (Moksha) as an immaterial and omniscient pure soul. However, contrary to divine providence, the only person responsible for the accumulation of karma is one’s own soul. The Jain philosophical tradition denies karmic mobility between souls [2] and instead places a strong emphasis on the individual’s responsibility for her spiritual development and eventual liberation.

The Jain understanding of karma is unique in comparison to other Indic karmic philosophies insofar as Jainism conceives of karma as a material force applicable to bonding with soulful beings with psychological, physiological, and environmental fruits/effects [6]. Psychological karmas have primary influence on the empirical, mundane soul, causing the delusion of faith, the determination of emotional states, and the obscuring of right knowledge and meaning. Physical karmas influence the type of body to which the soul will find attachement in the loka: heavenly, hellish, animal, plant, or human (man, woman, gender neutral). The environmental class of karmas determines the type of environment into which the embodied soul will be born: location, class, status, etc. The effects and fruits of karma cause the embodied soul to react a specific way due to how those karmic effects are manifested materially in accordance with the passions of the soul. Thus, the relationship between soul, body, and karma is intimate and circular: the empirical soul’s actions cause karmas that affect the empirical soul, which in turn lead to other actions of the empirical soul that cause karma, which in turn affect the empirical soul. S. C. Jain summarizes the conditioning role of karma in Jain philosophy when he states that “individuals differ among themselves in respect of their capacities, behaviour, material adjunct and the consequent feelings of pain and happiness. The principle of karma, as the believers of the doctrine think, just reveals the secret of such variations and differences” [6].

According to Jain philosophy, this karmic influx and bondage to a physical body as an empirical soul is foreign to the natural state of the jiva as a pure soul – the jiva in its liberated state – and so prevents the soul from realizing its eschatological goal of liberation from the reality of embodiment. Since achieving the liberation of the pure soul from continued transmigration between physical bodies is the intended goal of living existence, karma is the principle of limitation that obscures the powers of the pure soul from realizing this goal and the ways to achieve it through the cultivation of spiritual disciplines. Because Jainism holds that nothing that is intrinsic to the pure state of the soul can detrimentally impact its own identity, and because karma does so, Jain philosophy concludes that karma is alien to the state of the pure soul and so is to be mitigated against in this life through right faith, right conduct, and right knowledge: the three elements of Jain philosophy that are said to lay the path toward liberation [5, 10, 12].

The infinite cycle of karmic bonding and reincarnation is a presupposed postulate of the soul’s existence within the loka. There was never a time the soul was not bonded to a body in one of the four realms of existence: human, subhuman, heavenly, or hellish. There is no “fall from Grace” in an Augustinian sense (Cf. [6]) nor an existence of the soul in a pure state before karmic bonding. According to the Tattvarthasutra, “(The) soul, (the) non-soul, influx, bondage, stoppage, gradual dissociation and liberation constitute reality” (I. 4). Glasenapp [4] recognizes that this understanding involves an idea of eternal metempsychosis: “in each new existence actions which must be expiated in a future life are performed anew, so the migration of souls continues without end; but…every existence presupposes the actions of a preceding one, so likewise it is without a beginning” [4]. One may question why Jainism understands the soul to be alien to the body and karma alien to the soul in light of this “givenness” of bodily bondage. More importantly, one may seek to inquire as to the origin of the soul. But Glasenapp notes there is little evidence to suggest that such questions have been raised within the philosophical history of the Jain tradition [4].

But the philosophy of karma is only one part of Jain cosmology. The ethic of ahimsa (nonviolence) (see Ahimsa) is Jainism’s most defining characteristic and is metaphysically grounded within the Jain doctrine of karma and its eschatology of liberation. Jainism considers the ethic of ahimsa to be an eternal truth. The disclosure of this truth has been handed down by those who have achieved sufficient spiritual development to understand this eternal teaching and so have discovered the path to liberation. Interestingly enough, as will be discussed in greater detail below, the doctrine of karma itself functions to preserve the authority of the Jain tradition without need for a centralized religious authority. The ethic of ahimsa is therefore bound up with the metaphysics of karma so that right action in the world becomes instrumental in achieving liberation from this mundane, physically conditioned existence.

Although ahimsa has its immediate ethical application in terms of acting nonviolently and with compassion in our relationships with other living beings, it has metaphysical application insofar as ahimsa is the only weapon capable of fighting against karmic bondage that keeps the soul within the cycle of rebirth. The Tattvarthasutra mentions how the activity of the body (see Yoga) is physical, aural (speech), and mental in character (VI. 1). Moreover, it is the vibrations caused by this threefold activity that lead to the influx of karmas onto the empirical soul (VI. 2). Thus, the orientation of the Jain who has adopted ahimsa does so not only through vegetarianism but in all matters of action concerning mind, body, and speech. One can commit himsa (violence) through actions done by oneself, by persuading someone else to commit himsa, or condoning the violent action of others. Therefore, if one combines the three yogas with the three forms of karma, there are actually nine different ways one ought to practice ahimsa in one’s life to ensure the stoppage of the influx of karma to one’s soul [11]. Jainism extends ahimsa beyond the realm of one’s actions and into the realm of one’s thoughts and speech, since both may be vessels to promote, condone, or participate in violence. Ahimsa, therefore, is a universal orientation toward nonviolence in all forms of expression in order to fight against the law of karma that keeps one’s soul in bondage to the cycle of transmigration.

Although one can translate himsa as “violence,” given the relationship between himsa and the influx of karma due to one’s passions and attachment one can also understand the term to mean any form of activity, good or bad, executed by the embodied jiva. Because Jainism considers the soul to be alien to the body, because karma governs all embodied action within the universe, and because the influx of karma determines the nature and duration of karmic bondage, we see that action in its very nature creates attachment and causes the influx of karmas thus preventing the soul from attaining liberation. So an apparent paradox emerges within Jain philosophy: if one is to live a life of ahimsa, does this necessarily imply inaction in order to ensure the stoppage of karmic influx? After all, Jainism holds that those who have reached the highest level of spiritual development and attain the status of jinna attain total detachment in this life and so maintain a posture of meditation, inwardly focused on the soul and totally detached from his or her physical surroundings, until the point of liberation at death. In fact, the Tattvarthasutra mentions that “pure meditation is the direct cause of liberation” (A.IX.29.2). If all action necessitates the influx of karma, and the point of bodily life is to achieve the stoppage and dissociation of karmic influx, then how is charitable and compassionate action in thought, word, and deed not considered to be qualitatively negative insofar as charitable action and compassionate action must necessarily cause a karmic effect? If action equals karmic influx, then surely any action, good or bad, would only hinder the soul from attaining its proper end state of liberation. Vilas Sangave recognizes this conundrum when stating the common criticism leveled against the Jain perspective of ahimsa: “sometimes a charge is made against the doctrine of ahimsa to the effect that it is essentially negative in character in the sense that it always prohibits persons for doing certain activities. It is argued that in Jainism Ahimsa is treated as a mere abstention from himsa” [11, 13, 14]. So how does Jain philosophy resolve this conflict?

In addition to Jainism’s pragmatic solution to this conundrum in terms of the social division between householders and ascetics, Jainism provides a metaphysical solution found within the doctrine of karma itself. Jain karma theory distinguishes between auspicious and inauspicious karmas, the influx of which result in positive and negative karmic effects, respectively. The Tattvarthasutra recognizes both auspicious and inauspicious influx: “Virtuous activity is the cause of merit (punya) and wicked activity is the cause of demerit (papa)” (VI. 3). Moreover, this influx accruing activity pertains to the orientations of the passions of the person: if action is rooted in the passions of the body and so ultimately in attachment, then the karmic influx is transmigration extending (i.e., in accordance with demerit). If, however, action is rooted in detachment from the needs of the body and compassion for others, then the influx of “positive” karmas is transmigration reducing. In other words, wrong action causes the influx of those karmas that keep one in the cycle of rebirth, and right action causes the influx of those karmas that shorten the duration of the transmigratory cycle. The fact remains, however, that the fruit of virtuous action still becomes attached to the soul and must be lived out even if its purpose is only to shorten the length of inauspicious karmas through facilitating the process of karmic de-bonding. After all, just as a businessman must settle all his debts before he can make a profit, karmic influx must always be balanced and paid in full in order for the soul to attain liberation. Hence, actions done out of concern not for one’s own self and passions but concerned for the soul of another living being are considered auspicious and meritorious. These are the virtuous actions that include compassion, mercy, tolerance, etc. It is these auspicious actions that have the effect of reducing the karmic effects of the inauspicious actions one is still paying for throughout the duration of his or her life by incurring auspicious karma. However, given the strictures on karmic mobility [2, 8], such actions have no affect on the karmic state of the persons soul who is receiving the compassionate action. So though it is karma that accounts for cause and effect within Jain cosmology, the effects of these karmic causes are not necessarily negative. When the ethic of ahimsa is considered in tandem with Jainism’s metaphysics of karma, the “himsic-conditionedness” of reality emerges whether one understands himsa in terms of violence and nonviolence or action and inaction, it is impossible to live in a world without committing himsa or being forced to live out the consequences of the himsa committed by another. Karma, therefore, is the ethical, metaphysical, and cosmological law that governs the effects of himsa in this life.

Species, Causes, and Duration of Karmic Bonding

Relative to the Vedic and Buddhist traditions, Jainism is systematic in its development and classification of the doctrine of karma within its religious philosophy [4]. Karma does not apply to liberated souls (siddhas), permanent microorganisms (nigodas), or abhavyas, those jivas who are destined for a perpetual rebirth in the hellish realm and so are “unliberatable,” as it were. Karma can be understood broadly in four different ways according to (1) the manner of effect (prakrti), (2) the duration of effect (sthiti), (3) intensity of effect (rasa), (4) and the quantity or amount of accumulation. Given the soul’s state, there are eight primary species (mulaprakriti) of karmic matter capable of bonding to the soul:

• Jnanavaraniyakarma: obscures knowledge
• Darsanavarana karma: obscures undifferentiated cognition
• Vedaniya karma: produces the feeling of Joy and grief
• Mohaniya karma: obstructs belief and conduct
• Ayus karma: determines the duration of post-transmigration life
• Nama karma: determines an individual’s bodily features
• Gotra karma: determines the family surroundings one is born into
• Antaraya karma: hinders the soul in its capacity for resolution and enjoyment

Along with these 8 primary species, there are multiple subspecies (uttara prakrtis), which can be further subdivided resulting in around 148 different species of karma that are identified in Jain philosophy. There are two main divisions of the species of karma between obscuring (ghatiya) and non-obscuring (ghatiya), with the former hindering the soul and the latter being enjoyed by it. It is thus ghatiya karma that is the fruit of compassionate and merciful activity that accrue in acts of ahimsa, whereas ghatiya karma accrues and results from actions of violence based on the soul’s passion and attachment toward worldly things.

What is fascinating about the Jain understanding of karma is the systematic development of the particular karmic fruits borne out of the bonded karma as developed in the final five chapters of the Tattvartasutra (VI-X). For example, physical deformities are considered to develop from the influx of inauspicious physique-making karmas as a result of crooked activities (VI. 22); low social status is the result of self-praise and the censure and oppression of others, whereas high social status results from the opposite actions (VI. 25–26). Or consider the issue of religious authority within Jainism: Jainism holds the teachings handed down by the tirthankaras, acharyas, and ascetics in such high regard that the Tattvarthasutra asserts that “attributing faults to the omniscient, the scriptures, the congregation of ascetics, the true religion and the celestial beings leads to the influx of faith-deluding karmas” (VI. 13). Darsan mohaniya karma is said to be that karma which “causes a disturbance of the knowledge of religious truth in the jiva inherent by natural disposition” [4]. Moreover, it is mithyatva karma that causes complete unbelief and the ensuing heterodoxy. Thus, without need for a central authority to preserve the doctrines of the faith, Jainism safeguards its teaching against adulteration by appealing to an influx of karma that ensures the errancy of the “heretic” who is raising doubts about Jain teaching. The attribution of error to the heretic due to faith-deluding karma only reinforces one’s inability to question the foundations of Jain philosophy disclosed by the omniscient jinnas.

The duration of karma that remains bonded to the soul is called sthiti. Regardless of the type of karma bonded to the soul, minimal duration is considered auspicious: the purer the state of the soul along the 14 gunasthanas of spiritual development, the shorter the duration of karmic bonding. The effects of this bonding show their fruit according to the circumstances, and the intensity of the effects of karmic bonding that correspond to strengths and weaknesses congruent with the degree of the four passions (kasayas) of the soul (anger, deceit, greed, and pride) present in the particular jiva. These karmic particles are assimilated within the infinitely small space points (pradesas) within the jiva. Thus, karmic effects are said to hinder the soul because this karma is actually within and permeating the “ensouled space” of the jiva throughout its duration. Once this karma is assimilated within the space points of the jiva, it then takes on the many different species possible.

Karmic matter relates to the soul in terms of bandha (bondage), savara (stopping influx), and nirjara (disassociation). Bandha is the converted assimilated karmic matter within the jiva which forms a particular karmic species [4]. Similar to the concept of an electromagnetic field where atoms of opposite polarity are attracted to each other, Jain philosophy understands there to be the presence of something akin to an adhesive (sneha) between the jiva and the karma particles that lead to bonding. The four causes of bonding are (1) mithyatva (wrong belief), (2) avirati (lack of self-discipline in observance of vows), (3) kasayas (passions), and (4) yoga (activities). Thus, given the nature of all of these as forms of action, we can see that the causes of the activity of the jiva along with its corresponding karmic effect are synonymous and reciprocal concepts: all action, for better or for worse, bears karmic fruit.

There are two processes required for the shedding of karmic matter by the jiva: stoppage of karmic accumulation and dissociation of already possessed karmas. Because all karma must be “paid in full,” only the spiritual advancement of the jiva makes it possible for new karma to “fall off” the spiritually advanced soul so that ensuing action, done out of passionless detachment, though incurring an auspicious karmic influx, does not result in a bonding within the space points of the soul. This stoppage (sanvara) is of two types, psychic (bhava) and physical (dravya), and this stoppage is affected by the degree to which the jiva is able to exhibit control and restraint and exact carefulness in the observance of virtues, contemplations, endurance, and afflictions. These may be observed through both external austerities, such as fasting, solitude, physical mortification, and limitation of food-begging, and internal austerities such as expiation, reverence, selflessness, renunciation, and the internal contemplation of the soul through meditation. The means of achieving stoppage through such observances is explained in the Tattvarthasutra IX 4–18.

Nirjara or karmic de-bonding/dissociation is achieved through observing the force of austerities in order to acquire the infinite bliss of moksha over the banality of physical happiness. Karmic influx hinders this process, and so by the observance of austerities according to the vows taken by ascetic and householder alike, one can counteract the influx of karma that prevents one from achieving eternal happiness as a liberated soul. However, the force of the austerities must be greater than the force of karmic influx in order to achieve this goal. Thus, when one follows the de-bonding process through the observance of austerities, there is a gradual elimination of the forces of karmic attraction so that an aversion to karmic influx is achieved. When followed continuously throughout the many cycles of transmigration, the empirical soul is able to eliminate all of its accumulated karma achieving its natural state as a pure soul. When all of one’s karmic matter is de-bonded and annihilated, the soul is liberated and obtains omniscience (Tatt. X.2) and immediately travels to the uppermost realm of the cosmos, the siddhalok (Tatt. X.5), where the pure soul resides eternally detached from all passions, desires, relationships, or objects of knowledge. To know one’s soul completely as detached from all things through the destruction karmic impurities is to know all things omnisciently (Tatt. X.1). It is this type of knowledge the Tirthankaras are said to have within the Jain philosophical tradition.

Karma, Self-Reliance, and the Possibility of Karmic Mobility

What this brief survey of karma implies for Jain philosophy, then, is a strict form of self-reliance for the moral and spiritual progress of one’s soul. The jiva is the only thing responsible for its action within the world and only the jiva’s action in thought, word, and deed can prevent or encourage or hinder its liberation through the observance or neglect of austerities. Contrary to the Vedic understanding of karmic mobility as is seen in the funeral ritual of sraddha, wherein the son of a deceased parent offers food to be consumed by the Brahmanic priests as an offering to ensure the soul’s auspicious transmigratory journey to their next life, the philosophy of karma within Jainism denies the karmic efficacy of such actions on the part of others [2, 3, 8]. According to Jain karma theory, this very understanding as present in the ritual of sraddha is invalid because it involves a notion of merit transfer wherein another’s actions can impact the karmic state of another’s soul either in this life or the next. But as has already been noted above, Jains hold one’s soul to be the sole guarantor of its liberation; one cannot take on another’s karmic burden as her or his own. Moreover, where the Vedic tradition asserts a period of time after death where the soul is not immediately reincarnated, Jainism denies this and holds that the soul immediately occupies a new bodily form in one of the four possible realms (human, animal, heavenly, or hellish) upon death. One can therefore see a direct relationship between Jainism’s systematic development of a karmic philosophy that ensures the soul’s immediate reincarnation in a new body and a rejection of Brahmanic authority as an extension of the sramanic tradition: “Since only in the Brahmans do we see the fattened bellies; and transference of these into theirs (ancestors?) cannot be espied; and only because on the part of the Brahmans is satisfaction witnessed” [8]. If Jain philosophy states that a soul immediately occupies a new body at the point of death, then the ritual of sraddha is unnecessary for it has no impact on where and how the soul will be reborn. Instead, Jainism holds that rebirth circumstances are entirely determined by the karma one has accumulated, shed, or retained, throughout his or her life. Hence, from a position of history and sociology, one can interpret the systematic development of the Jain philosophical understanding of karma to invalidate Brahmanic authority and cultural conventions that require what is essentially a “karmic tax” to be paid on the part of the layperson as is indicated in the example of the funeral rite of sraddha.

Philosophy aside, however, there is evidence to suggest that Jainism’s strict denial of karmic mobility is merely theoretical in character. According to Cort [2003], there is evidence of an understanding of incidental and intentional merit transfer of karmic effects throughout the history of the Jain tradition in terms of prayers for the deceased and other ritual activities. Though Jain philosophy may deny the possibility of karmic mobility according to its systematic development in the Tattvarthasutra and its philosophical tradition, nevertheless karma theory is shown to be more malleable and dynamic when applied in Jain religious life. Moreover, there are members within the Jain community today such as Subhash Jain [7] who are reconsidering the doctrine of karma in order to reconcile the doctrine with perceived inconsistencies that have emerged with advances in knowledge about the functioning of the natural world, human physiology, and human psychology