In the MaWangDui YiJing this trigram has the name Gan: pay taxes. A distress that will come back again and again, and certainly in old times it could be life-threatening. Its other meaning is to pay for the music, maybe also like 'to pay the piper'. 

Shaping power, the element of Kan
"God (Di) toils in the sign of Kan"

  Water is the reason why bodies have a pattern of build, and minds as well, which is everywhere on the earth basically similar. They are all shaped by the same forces of universe, passed on to them by the water. Water is a huge source of creativity and love. It passes heaven's possibilities on, so one can draw from it without ever exhausting it. It will forever challenge, it is impossible to fathom its depth. When we follow its movements, we follow our dao.

"Kan is water, .. bending and straightening out, bow and wheel."

  Two important influences, which are always present, are gravity and rhythm. Water has no direction of its own, it obeys universal law, so it flows downward, and always in rhythmic ways. The way of water looks like the way of snakes, winding, coiling. Emotions, organs, all living matter don't know straight paths either, they grow and move in spirals.

"Water and fire do not combat each other" (Lynn: do not fail to complement each other/ drive each other on).

  Water is the 'shaper-giver', fire is its manifestation. In the mind water is the realm of feelings, sadness, remembering and loneliness. It is hard labor, midnight, midwinter, and the unconscious. But also inner wisdom, inner truth. They need fire to reach the surface. Dreams reflect the shapes of the night into day-light of consciousness, like the moon reflectings the light of the sun.

"It manifests itself in the ear"

  Water resonates with influences and vibrations and stores them. Water which has been disturbed at a certain moment will long afterwards carry the influences of that particular moment. Water is also sound, especially of percussion, it is rhythm and pattern.

"It is penetration, the moon"

  We consist of 70% or more of water, heaven uses water to 'tell' us things. The moment of birth stays with us as our horoscope, a moment of shock is remembered for years after. The moon brings the tides into our body and mind.

"It is dangerous"

  Fears, trauma's, nostalgia, empathy, intuition, courage, they all depend on water, both for embedding them in us, and their release.

"Among men it means the melancholy, those with sick hearts"

  The depth of our soul is like the depth of an ocean, dark and mysterious, dangerous and source of life. The place where our emotions are shaped. Nothing is static there, it is ever flowing and changing.

Inner and outer trigram
Water "moves according to principles and virtue,
it uses repeating to teach practice"

  When Water is INNER (lower) trigram it makes things flow into their inherent pattern using the abilities of the outer trigram.
 In 6 the powerful order of Heaven (A noble one, when he sets up affairs, plans ahead)
  In 7 the generous space of Earth (The noble one tolerates the common people and watches over the crowds)
  In 40 the energy of Thunder (A noble one pardons transgressions and is lenient towards crimes)
  In 59 the influence of Wind (A noble one delimits number and measure and deliberates upon ethical conduct).
  In 29 the patterns of Water (The noble one moves according to principles and virtue, he uses repeating to teach practice)
  In 64 the clarity of Fire (A noble one is cautious when differentiating things so that each finds its place).
  In 4 the reality of Mountain (A noble one nurtures virtue by reliable conduct)
  In 47 the reflection of Lake (A noble one incurs fate on fulfilling his aspiration)

  When Water is OUTER (upper) trigram it lets the qualities of the inner trigram flow into their inherent shape.
  In 5 the powerful order of Heaven (The noble one drinks and eats and reposes relaxed)
  In 8 the generous space of Earth (The ancient kings founded innumerable territories, maintaining close relations with the feudal lords)
  In 3 the energy of Thunder (The noble one unravels the warp)
  In 48 the influence of Wind (The noble one encourages the toiling people to stand by each other)
  In 29 the (re)shaping power of Water (The noble one moves according to principles and virtue, he uses repeating to teach practice)
  In 63 the clarity of Fire (The noble one takes thought of misfortune and guards against it)
  In 39 the reality of Mountain (The noble one reverses his being to repair the character)
  In 60 the reflection of Lake (The noble one delimits number and measure and deliberates upon ethical conduct)