Separation of most layers of the retina of the eye from the choroid, the pigmented middle layer of the eyeball. With age, small tears can develop in the retina, and the vitreous humour inside the eyeball leaks through, separating the retina from the choroid. The disease retrolental fibroplasia or accidents can also cause retinal detachment. It usually develops slowly, without pain. Floating black spots and flashes of light appear in the affected eye, and vision becomes increasingly blurred. Without prompt treatment, it causes permanent blindness. Draining the fluid behind the retina and applying heat, a laser beam, or extreme cold causes scarring that seals the tears and prevents the retina from detaching again.

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Detachment is a state in which a person overcomes his or her attachment to desire for things, people or concepts of the world and thus attains a heightened perspective. Detachment as release from desire and consequently from suffering is an important principle in Hinduism, Buddhism, the Bahá'í Faith and Kabbalah.

The Hindu view of detachment requires further explanation. It comes from the understanding of the nature of existence and the true ultimate state sought is that of being in the moment. In other words, while one is responsible and active, one does not worry about the past or future. The detachment is towards the result of ones actions rather than towards everything in life.

Lao Tzu's "Tao Te Ching" expressed the concept (in chapter 44) as:

Fame or Self: Which matters more? Self or Wealth: Which is more precious? Gain or Loss: Which is more painful? He who is attached to things will suffer much. He who saves will suffer heavy loss. A contented man is rarely disappointed. He who knows when to stop does not find himself in trouble. He will stay forever safe.