The Wheel of Life
The Wheel of Life is a representation of the Buddhist teaching on the suffering and impermanence of cyclic existence.
The traditional Wheel of Life thangka presents a large circle which consists of three more concentric circles within and six segments. Turning (or devouring?) this large circle is Yama, the Lord of Death, a fierce-looking figure whose head protrudes above the circle and his feet below. His incisors are fang-like and his hands and feet are taloned. Skulls adorn his head, indicating his association with death.
The Innermost Circle
The innermost circle of the Wheel of Life are three animals - a pig, a rooster and a snake, representing greed (lobha), hatred (dosa) and delusion (moha). These are referred to as 'the three fires' or 'the three poisons'. The fact that these are positioned at the very center of the Wheel of Life indicates how fundamental they are in sustaining the cycle of birth and death with all its attendant suffering. The pig represents delusion, the rooster greed and the snake hatred.
The Inner Circle
The circular band surrounding the center of the Wheel shows beings rising and falling according to their deeds (the law of kamma). Those who lived good lives are seen to be ascending, those who have lived bad lives, descending. The background is light for those ascending and dark for those on the descent.
The Six Realms
Moving outwards, the Wheel is split into six segments, each segment depicting one of the six realms of samsara, the cycle of birth and death. Starting clockwise at the top there is the realm of the gods, a place of pleasure and happiness. Figures playing musical instruments - suggesting a life of leisure and sensory delight - are often depicted within this segment. It should be noted, however, that this is not an everlasting abode, and so too with the others. Once a god's store of good deeds has been used up, that god is destined to rebirth in a lower realm.
The second segment portrays the realm of what are variously referred to as demi-gods or titans. Though powerful, they live a flawed existence due to their jealousy which causes them to compete with each other.
The third segment moving clockwise shows the realm of the hungry ghosts or pretas. These are shown with distended bellies, though no
matter how much they eat and drink, they are always thirsty and hungry.
The bottom segment shows the hell realm, where beings live tormented by extremes of heat and cold. Though not an eternal realm, the opportunities for good actions are limited so it is difficult for a being to escape from this realm easily.
The fifth segment is the animal realm dominated by instinct and a need to survive, and in which opportunities for moral action are, as in hell, limited.
The final realm is that of humans - a place that has pleasant aspects and some unpleasant ones too. Of the six, Buddhism regards this as the best realm of all in that it offers the best conditions for gaining enlightenment. Unlike the realm of the gods, humans are able to focus on other things rather than just sensory pleasure. The vicissitudes of life mean that it is inevitable that humans will see the realm they inhabit as less than satisfactory and therefore seek answers. It is thus a place where there are opportunities for both moral action and spiritual advancement. It is for this reason Buddhism emphasizes how precious it is to be born a human being and how important it is to take advantage of the special opportunities it affords, opportunites denied the other five realms.
In many Wheel of Life thangkas, a bodhisattva is depicted in each of the six realms, suggesting that compassionate beings are in each of the realms to help those who are there.