Karma (Sanskrit: कर्म) originated in the Vedic system of religion, otherwise known as Hinduism. As a term, it can at the latest be traced back to the early Upanishads, around 1500 BCE. In its major conception, karma is the physical, mental and supramental system of neutral rebound, "cause and effect" that is inherent in existence within the bounds of time, space, and causation. Essentially what this means is that the very being which one experiences on (as a human being) is governed by an immutable preservation of energy, vibe, and action.
Karma, for these reasons, naturally implies reincarnation or rebirth (though the opposite is not true) since thoughts and deeds in past lives will affect one's current situation. Thus, every individual alike is responsible for the tragedies and good 'fortunes' which are experienced. The concept of an inscrutable "God" figure is not necessary with the idea of karma. It is vital to note that karma is not an instrument of a god, or a single God, but is rather the physical and spiritual 'physics' of being. As gravity governs the motions of heavenly bodies and objects on the surface of the earth, karma governs the motions and happenings of life, both inanimate and animate, unconscious and conscious, in the cosmic realm.
Thus, what certain philosophical viewpoints may term "destiny" or "fate" is in actuality, according to believers of karma, the simple and neutral working out of karma. Many have likened karma to a moral banking system, a credit and debit of good and bad. However, this view falls short of the idea that any sort of action (action being a root meaning of 'karma'), whether we term it 'good' or 'bad', binds us in recurring cause and effect. In order to attain supreme consciousness, to escape the cycle of life, death, and rebirth and the knot of karma one must altogether transcend karma. This method of transcendence is variously dealt with in many streams of not only Hinduism and Buddhism, but other faiths and philosophical systems as well.
From Hinduism the concept of karma was absorbed and developed in different manners in other movements within the other Indian religions of Buddhism, Jainism, and Sikhism. Although these religions express significant disagreement regarding the particularities of "karma", all four groups have relatively similar notions of what karma is. More recently the concept has been adopted (with various degrees of understanding) by many New Age movements, Theosophy and Kardecist Spiritualism.
Karma in the Dharma-based Religions
Karma came into being in Hinduism, based on the Vedas and Upanishads. One of the first and most dramatic illustrations of Karma can be found in the great Hindu epic, the Mahabharata. The original Hindu concept of karma was later enhanced by several other movements within the religion, most notably Vedanta, Yoga, and Tantra.
Hinduism sees karma as immutable law with involuntary and voluntary acts being part of a more intricate system of cause and effect that is often not comprehensible to one bound by karma. It is the goal of the Hindu, as expressed succinctly in the Bhagavad Gita, to embrace a 'sattvic' lifestyle and thus avoid creating more karma (karma is not qualified as good or bad). By ceasing to create more karma, the jiva-atma or individual soul is able to move closer to Moksha, or liberation.
To the Hindu, karma is the law of the phenomenal cosmos that is part and parcel of living within the dimensions of time and space. All actions, thoughts, vibrations of any sort, are governed by a law that demands perfect rebound. So all jiva-atmas (individual souls) must experience karma if they live and experience the phenomenal universe. To escape the cycle of life, death and rebirth, one must exhaust one's karma and realize one's true Self as the highest truth of Oneness that is Brahman (or for dvaitists (dualists) bliss with the Supreme Godhead). In Hinduism, karma is of three kinds:
This karma is unchangeable within the scope of one life, since it is the 'setup' for the life in question. It is the karma of one's past lives. After death, the atma leaves the body, as the casting off of old vestments, and carries with it the samskaras (impressions) of the past life of thoughts and actions and events. These samskaras manifest themselves in the unchangeable situation into which one is born and certain key events in one's life. These include one's time of death (seen as governed by an allotment from birth of the total number of one's breaths for that life), one's economic status, one's family (or lack of family), one's body type and look: essentially, the setting of one's birth, the initial base.
The samskaras that one inherits from the last lives create one's personality, inclinations, talents, the things that make up one's persona. One's likings, abilities, attitudes and inclinations are based on the thoughts and actions of past lives. One's samchita karma is somewhat alterable through practice and effort towards change. This might be seen through the Hindu system of Yoga and the dynamic of the gunas. An example would be someone who, through meditation, slowly evolved into a more stable personality.
Agami karma is the karma of the present life over which the soul has complete control. Through it one creates one's karma in the present for the future of the current life and in life-times to come.
The Hindu cannot say, sometimes, if a major event in life is the doing of Prarabadha or Agami Karma. The idea of "bad things happening to good people" is seen by the Hindu as a result of Prarabadha Karma, more simply understood as karma from a past life. In Hinduism, karma works within a cyclical framework that sees the phenomenal universe being created and eventually dissolving back into itself, back into realization that it was nothing other than Maya imposed on the truth of Brahman. So Karma will eventually be worked out.
Karma does allow for anirudh (Divine Grace). Through exceeding devotion and love of God, the Hindu believes one can be helped to speed through Karma phal (Karmic fruit). By developing 'vairagya' or 'detachment' from the fruits of one's karma, as Lord Krishna most famously summarized, one can transcend karma and be liberated. One is aided by love of God. All the Yogas of Hinduism seek to transcend karma through different means of realization.
In Buddhism, only intentional actions are karmic "acts of will". The 'Law of Karma' refers to "cause and effect", but Karma literally means "action" - often indicating intent or cause. Accompanying this usually is a separate tenet called Vipaka, meaning result or effect. The re-action or effect can itself also influence an action, and in this way, the chain of causation continues ad infinitum. When Buddhists talk about karma, they are normally referring to karma/action that is 'tainted' with ignorance - karma that continues to ensure that the being remains in the everlasting cycle of samsara.
This samsaric karma comes in two 'flavours' - 'good' karma, which leads to positive/pleasurable experiences, like high rebirth (as a deva, asura, or human), and bad karma which leads to suffering and low rebirth (as a hell-sufferer, as a preta, or as an animal). There is also a completely different type of karma that is neither good nor bad, but liberating. This karma allows for the individual to break the uncontrolled cycle of rebirth which always implies suffering, and thereby leave samsara to permanently enter Nirvana.
The Buddhist sutras explain that in order to generate liberating karma, we must first develop incredibly powerful concentration, and proper insight into the (un)reality of samsara. This concentration is akin to the states of mind required to be reborn in the Deva realm, and in itself depends upon a very deep training in ethical self-discipline.
This differentiation between good karma and liberating karma has been used by some scholars to argue that the development of Tantra depended upon Buddhist ideas and philosophies. Understanding the universal law of Karma provides order to a beginningless and endless universe. Alongside this view is the related notion of Buddhist rebirth - sometimes understood to be the same thing as reincarnation - which has its roots in the principle of Karma.
Jains believe that karma is a form of matter. Mahavira described karma as "clay particles". Jains do not believe in "good karma" or "bad karma"; they try to avoid all karma.
Although, the Karma can not be proven as easily as the law of gravity, millions of people believe in it and is a part of many cultures and psyche of groups of people. Even more people, without a religious background, especially in a western culture, come to the conviction of the existence of Karma. For some, karma is a more reasonable concept than eternal damnation for the wicked. Spirituality or a belief that virtue is rewarded and sin creates suffering; eventually leads to a belief in Karma. With any law, it is better to obey the law even if one doesn't believe in it and ignorance does not grant immunibility or one learns the hard way. A common expression heard is 'It's unfair' by those ignorant of Karma. A study in Karma reveals that is every thing is fair but again that depends one's conviction.
According to Karma, performance of positive action results with the reaction of a good conditioning in one's experience, whereas a negative action results in a reaction of a bad response. This may be an immediate result following the act, or a delayed result occurring either in the present life or the next. Thus, meritorious acts may create rebirth into a higher station, such as a superior human being or a godlike being, while evil acts result in rebirth as a human living in less desirable circumstances, or as a lower animal. While the action of karma may be compared with the Western notions of sin and judgment by God or gods, Karma is held to operate as an inherent principle of the Universe without the intervention of any supernatural being.
Most teachings say that for common mortals, having an involvement with Karma is an unavoidable part of day-to-day living. However, in light of the Hindu philosophical school of Vedanta, as well as Gautama Buddha's teachings, one is advised to either avoid, control or become mindful of the effects of desires and aversions as a way to moderate or change one's karma (or, more accurately, one's karmic results). An interesting similarity is found between the concept of the 'law of Karma' and the law in Westerns physics which says 'action is reaction'. One could argue that the law of Karma is the mental equivalent of this law in physics.
New Age and Theosophy
The idea of karma was popularized in the west through the work of the Theosophical Society. Kardecist and Western New Age reinterpretations of karma frequently cast it as a sort of luck which is associated with virtue: if one does good or spiritually valuable acts, one deserves and can expect good luck; contrariwise, if one does harmful things, one can expect bad luck or unfortunate happenings. In this conception, karma is affiliated with the Neopagan law of return or Threefold Law, the idea that the beneficial or harmful effects one has on the world will return to oneself.