Carl Jung's Life/Death Parabola
- "Life is an energy process. Like every energy-process, it is in principle irreversible and is therefore directed towards a goal. That goal is a state of rest. [...] The end of every process is its goal.
- "With the attainment of maturity and at the zenith of biological existence, life's drive towards a goal in no wise halts. With the same intensity and irresistibility with which it strove upward before middle age, life now descends; for the goal no longer lies on the summit, but in the valley where the ascent began. The curve of life is like the parabola of a projectile which, disturbed from its initial state of rest, rises and then returns to a state of repose.
- "The psychological curve of life, however, refuses to conform to this law of nature. Sometimes the lack of accord begins early in the ascent. The projectile ascends biologically, but psychologically it lags behind. [...] Our psychology then loses its natural basis. Consciousness stays up in the air, while the curve of the parabola sinks downward with ever-increasing speed.
- "Natural life is the nourishing soil of the soul. Anyone who fails to go along with life remains suspended, stiff and rigid in midair. [...] From the middle of life onward, only he remains vitally alive who is ready to die with life. For in the secret hour of life's midday the parabola is reversed, death is born. The second half of life does not signify ascent, unfolding, increase, exuberance, but death, since the end is its goal. The negation of life's fulfilment is synonymous with the refusal to accept its ending. Both mean not wanting to live, and not wanting to live is identical with not wanting to die. Waxing and waning make one curve.
- "Like a projectile flying to its goal, life ends in death. Even its ascent and its zenith are only steps and means to this goal." 
- Carl Jung, "The Soul and Death", pp. 405-408, from Volume 8 of the Collected Works of C.G. Jung: The Structure and Dynamics of the Psyche