Kitsune is the Japanese word for fox. Foxes are a common subject of Japanese folklore; in English, kitsune refers to them in this context. Stories depict them as intelligent beings and as possessing magical abilities that increase with their age and wisdom. Foremost among these is the ability to assume human form. While some folktales speak of kitsune employing this ability to trick others—as foxes in folklore often do—other stories portray them as faithful guardians, friends, lovers, and wives.
It is widely agreed that many fox myths in Japan can be traced to China, Korea, or India. Chinese folk tales tell of fox spirits called huli jing that may have up to nine tails, or Kyūbi no Kitsune in Japanese. Many of the earliest surviving stories are recorded in the Konjaku Monogatari, an 11th-century collection of Chinese, Indian, and Japanese narratives.
Kitsune are believed to possess superior intelligence, long life, and magical powers. They are a type of yōkai, or spiritual entity, and the word kitsune is often translated as fox spirit. However, this does not mean that kitsune are ghosts, nor that they are fundamentally different from regular foxes. Because the word spirit is used to reflect a state of knowledge or enlightenment, all long-lived foxes gain supernatural abilities.
There are two common classifications of kitsune. The zenko (literally good foxes) are benevolent, celestial foxes associated with the god Inari; they are sometimes simply called Inari foxes. On the other hand, the yako (literally field foxes, also called nogitsune) tend to be mischievous or even malicious. Local traditions add further types. For example, a ninko is an invisible fox spirit that human beings can only perceive when it possesses them. Another tradition classifies kitsune into one of thirteen types defined by which supernatural abilities the kitsune possesses.
Physically, kitsune are noted for having as many as nine tails. Generally, a greater number of tails indicates an older and more powerful fox; in fact, some folktales say that a fox will only grow additional tails after it has lived 100 years. One, five, seven, and nine tails are the most common numbers in folk stories. When a kitsune gains its ninth tail, its fur becomes white or gold. These kyūbi no kitsune (nine-tailed foxes) gain the abilities to see and hear anything happening anywhere in the world. Other tales attribute them infinite wisdom.
Kitsune may take on human form, an ability learned when it reaches a certain age—usually 100 years, although some tales say 50. As a common prerequisite for the transformation, the fox must place reeds, a broad leaf, or a skull over its head. Common forms assumed by kitsune include beautiful women, young girls, or elderly men. These shapes are not limited by the fox's age or gender, and a kitsune can duplicate the appearance of a specific person. Foxes are particularly renowned for impersonating beautiful women. Common belief in medieval Japan was that any woman encountered alone, especially at dusk or night, could be a fox. Kitsune-gao or fox-faced refers to human females who have a narrow face with close-set eyes, thin eyebrows, and high cheekbones. Traditionally, this facial structure is considered attractive, and some tales ascribe it to foxes in human form. Variants on the theme have the kitsune retain other foxlike traits, such as a coating of fine hair, a fox-shaped shadow, or a reflection that shows its true form.
In some stories, kitsune have difficulty hiding their tails when they take human form; looking for the tail, perhaps when the fox gets drunk or careless, is a common method of discerning the creature's true nature. A particularly devout individual may in some cases even be able to see through a fox's disguise merely by perceiving them. Kitsune may also be exposed while in human form by their fear and hatred of dogs, and some become so rattled by their presence that they revert to the form of a fox and flee.
Other supernatural abilities commonly attributed to the kitsune include possession, mouths or tails that generate fire or lightning (known as kitsune-bi; literally, fox-fire), willful manifestation in the dreams of others, flight, invisibility, and the creation of illusions so elaborate as to be almost indistinguishable from reality. Some tales speak of kitsune with even greater powers, able to bend time and space, drive people mad, or take fantastic shapes such as a tree of incredible height or a second moon in the sky. Other kitsune have characteristics reminiscent of vampires or succubi and feed on the life or spirit of human beings, generally through sexual contact.
Kitsunetsuki literally means the state of being possessed by a fox. The victim is always a young woman, whom the fox enters beneath her fingernails or through her breasts. In some cases, the victims' facial expressions are said to change in such a way that they resemble those of a fox. Japanese tradition holds that fox possession can cause illiterate victims to temporarily gain the ability to read. Though foxes in folklore can possess a person of their own will, Kitsunetsuki is often attributed to the malign intents of hereditary fox employers, or tsukimono-suji.
In Japan, kitsunetsuki was noted as a disease as early as the Heian period and remained a common diagnosis for mental illness until the early 20th century. Possession was the explanation for the abnormal behavior displayed by the afflicted individuals. In the late 19th century, Dr. Shunichi Shimamura noted that physical diseases that caused fever were often considered kitsunetsuki. The belief has lost favor, but stories of fox possession still occur, such as allegations that members of the Aum Shinrikyo cult had been possessed.
In medicine, kitsunetsuki is a culture-bound syndrome unique to Japanese culture. Those who suffer from the condition believe they are possessed by a fox. Symptoms include cravings for rice or sweet red beans, listlessness, restlessness, and aversion to eye contact. Kitsunetsuki is similar to but distinct from clinical lycanthropy.
Depictions of kitsune or their possessed victims may feature round or onion-shaped white balls known as hoshi no tama (star balls). Tales describe these as glowing with kitsune-bi, or fox-fire. Some stories identify them as magical jewels or pearls. When not in human form or possessing a human, a kitsune keeps the ball in its mouth or carries it on its tail. Jewels are a common symbol of Inari, and representations of sacred Inari foxes without them are rare.
One belief is that when a kitsune changes shape, its hoshi no tama holds a portion of its magical power. Another tradition is that the pearl represents the kitsune's soul; the kitsune will die if separated from it for long. Those who obtain the ball may be able to extract a promise from the kitsune to help them in exchange for its return.