Cancer the Crab -- http://www.skyscript.co.uk/cancer.html
As the sign of the Crab, the psychological traits of Cancer are characterised by the image of a creature with a tough, hardened shell protecting a soft and vulnerable centre. Cancer is ruled by the Moon and belongs to the element of water. Unlike most signs, which share their planetary rulers, Cancer claims exclusive rights to the Moon, both sign and planetary ruler termed 'cold and moist' in nature. Understanding the essence of that phrase reveals a lot about the complex sensitivity that lies beneath the Cancerian's thick, crustaceous shell.
In ancient astrology the condition of 'moistness' was viewed as the capacity to release emotions and connect with other beings. Moisture blurs the boundaries that define us as distinct individuals, allowing empathy, sympathy and a shared experience of personal or collective events. The act of sharing emotions represents an important aspect of forming bonds and unions, so moisture is also a creative condition, which forms the basis of love, fertility and reproduction. When we become too emotional the natural reaction is to release the 'excess of water' through the shedding of tears.
Hence, water as an element relates to the emotions and the world of feelings. It is a passive, absorbing element; receptive and keenly perceptive. The energy of water is fluid, unshaped, lacking consistency in definition and structure, but remarkable in its ability to seep into inaccessible places and change its form - sometimes appearing as vaporous as steam, sometimes as cold and solid as ice. The use of the word cold when applied to this element could never imply that there is insensitivity to feelings or detachment from emotions, but that the energy is passive, not active. Water 'types' are not quickly stirred to heated debate or dynamic, self-assertive action. Their tendency is to wait, reflect and absorb, responding to circumstances and remaining responsive to the needs of others and the changing demands of life's events.
In the water signs of Scorpio and Pisces we see a different expression of this energy. Scorpio symbolises the stillness of the murky depths, areas so deep and dark that no movement occurs without the disturbance of long-accumulated sediment. Pisces, associated with the linear flow of the river, suggests a more immediate response to collective movement, trends and ideals. Lacking the hardened shell of the other water types, Pisces signifies a sensitive energy, easily impressed upon by its immediate environment. But Cancer, taking its habitation on the shore of the ocean, and governed by the Moon, responds to the cyclic and rhythmic rise and fall of life's ebb and flow. This sign is known for its moodiness, so Cancerians can be up one day and down the next, responding to the joys and pains of the world in a pattern that can (superficially) seem to bear little relation to the immediate events around them.
Since Cancer finds its strength in instinctive, emotional responses, Cancerians are known for their remarkable psychic sensitivity, absorption of memories and receptiveness to emotional impressions. This is widely accepted as one of the most psychic signs of the zodiac and there is usually a marked interest in the occult, a vivid recollection of powerful dreams, and strong symbolic appreciation. But such an acute sensitivity to their physical and unconscious environment is a double-edged sword, and awareness of complex psychological factors that underlie apparently simple acts make it difficult for Cancerians to apply their will and foster their own self-interests unfettered by feelings of guilt and torn sympathies. This hesitancy and vulnerability to emotional impacts on themselves and others has given the sign a reputation for weakness, and a lack of ability to apply direct action to direct problems.
In addition, this sign is one that dislikes glares of publicity and is rarely comfortable at the centre of attention. Traditional descriptions of the sign depict it as 'dark' and nocturnal, lacking in vibrancy. The astronomical foundation for this is that the constellation Cancer is a particularly dark and dimly lit region of the sky. It has few distinguishable stars and is mainly notable for a nebulous, cloud-like cluster which ancient astronomers regarded as an area where energies were dissipated. The connection with the element of water and the rulership by the Moon reinforces the ancient foundation of this reputation. The water element relates to the phlegmatic humour, which seeks to retain its energies and inclines towards lethargy, while association with the Moon adds to the sense of inconstancy and irrational or unreasonable behaviour - or behaviour that seems strange when evaluated solely by reason or the rational faculties.
The more negative traits associated with this sign then, are physical weakness, lethargy bordering on laziness, a chaotic and unorganised application of methods (often the cause of associated sloppiness and untidiness in the home and dress), and a moodiness that is hard for others to relate to or fully understand. Cancer generally has a dislike of discipline, aptly symbolised by a creature that lacks an internal skeletal structure, but the Cancerian way of dealing with that is simply to avoid issues; there is little inclination towards rebellious acts or direct and open confrontations.
The symbolism of the celestial crab also gives an insight into the way that Cancerians move through life, react to situations and respond to problems. Cancer is one of the few constellations that rises backwards in the zodiac. The Sun's entry into Cancer occurs at the summer solstice - a term derived from the appearance of the Sun 'standing still' as it approaches this point. The creature itself, of course, is known for its sidewards gait. So the movement associated with Cancer is a strange one, revealing a sense of hesitancy, a sidewards approach to things,