Death is the end of life in an organism. All biological and living activity of the living thing stop, including the mind and the senses. The usual signal for death is that the heart stops beating and cannot be restarted. This can be caused by many things. All living things have a limited lifespan, and all living things eventually die.
Living things which have died are normally described as being dead. Death of humans is often investigated for the cause, in case of crime (such as murder) or disease that may continue to kill other humans. About 150,000 people die every day around the world. About two thirds of these people die because of age. In addition to the physical body, some believe humans also have a soul and believe that the soul can continue without a body (afterlife), move into another body (reincarnation), or cease to exist (annihilationism). Religions have different beliefs about this issue. Many cultures have their own customs and rituals to respect the dead.
When people talk about things or events that lead to the death of a plant or animal, those things or events are usually described as being deadly, or fatal. In the case of diseases, they are described as terminal. Humans are no different from any other lifeform. Our bodies have an ability for self-repair, but that ability is limited. Finding the cause of death is a medical speciality called pathology. In medicine, death is when the heart stops beating for more than several minutes. There are special times in which people recover even though the heart has stopped for 30 minutes, such as near-drowning in very cold water. If machines are used to help the heart and lungs work, then the moment of death is more difficult to know.
Society and culture
Death is commonly a sad or unpleasant thing to people. It can make people think about their own death. People might miss the person who has died. They might also be sad for the family and friends of the person who has died.
Religious views of death
For a long time, many people have been afraid of death and a lot of people have wondered about what may happen to people after they die. This is one of the largest questions of philosophy and religion. Many people believe there is some form of afterlife.
Christianity has a special focus on death because of the state killing of Jesus Christ by the Romans. In Islam this is thought to demonstrate the injustice of human systems of dealing out death, and the ability of the best people to overcome it and even forgive it. In Christianity itself it is thought to prove that Jesus himself was really God and so could lose his body and still have the power of resurrection. In Buddhism reincarnation is believed to occur. Reincarnation is an idea taken from Hinduism.
Preparing for death
Aside from wills, goodbyes, organ donations and funerals, there is important personal experience to decide to pass on, or not, when someone knows they may soon die. Palliative care focuses on basic decisions people make when they are very close to the end of their lives, and it ensures someone is always available to talk to them. It is a replacement for heroic medical intervention that may keep them physically alive but with no quality of life. Human psychology must prepare for death if it is anything other than a quick surprise:
Elizabeth Kubler-Ross wrote that there were several stages in dying, of which denial was the first, and acceptance was the last. Recording one's life is often something people with acceptance will do to leave a memoir or a full autobiography:
Because events leave living memory, and may only be part of oral tradition, there are projects to record everything that people remember about World War I and the Shoah. The first of these was to record everything remembered about the U.S. Civil War. This discipline has changed history since we have so many more first person accounts of the times, and made social history much more standard.
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