From NewScientist:
IT'S said that when a general returned in glory to ancient Rome, he was accompanied in his procession through the streets by a slave whose job it was to remind him that his triumph would not last forever. “Memento mori,” the slave whispered into the general's ear: “remember you will die”. The story may be apocryphal, but the phrase is now applied to art intended to remind us of our mortality – from the Grim Reaper depicted on a medieval clock to Damien Hirst's bejewelled skull. As if we needed any reminder. While few of us know exactly when death will come, we all know that eventually it will. It's usual to talk about death overshadowing life, and the passing of loved ones certainly casts a pall over the lives of those who remain behind. But contemplating our own deaths is one of the most powerful forces in our lives for both good and ill (see “Death: Why we should be grateful for it“) – driving us to nurture relationships, become entrenched in our beliefs, and construct Ozymandian follies.
In this, we are probably unique. Most animals seem to have hardly any conception of mortality: to them, a dead body is just another object, and the transition between life and death unremarkable. We, on the other hand, tend to treat those who have passed away as “beyond human”, rather than “non-human” or even “ex-human”. We have developed social behaviours around the treatment of the dead whose complexity far exceeds even our closest living relatives' cursory interest in their fallen comrades. Physical separation of the living from the dead may have been one of the earliest manifestations of social culture (see “Death: The evolution of funerals“); today, the world's cultures commemorate and celebrate death in ways ranging from solemn funerals to raucous carnivals. So you could say that humans invented death – not the fact of it, of course, but its meaning as a life event imbued with cultural and psychological significance. But even after many millennia of cultural development, we don't seem to be sure exactly what it is we've invented. The more we try to pin down the precise nature of death, the more elusive it becomes; and the more elusive it becomes, the more debatable our definitions of it (see “Death: The blurred line between dead and alive“).
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