Safe to say we all want to live a long full life.  Grandad live to be 96, my dad 83. But how long is long enough?   If technology could make it happen, would you really want to live forever?

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An average man born in 1800 had a life expectancy of 35 years. In 1900, he would have made it all the way to 47. By 1950, average life expectancy was up to 68 years, and now it's up to 78.

The trend is definitely favorable. But how long would you want to go on for?