Do Immortal Human Beings Exist?

In 1997, Jean Calmet of France, the authentically verified oldest person in the world died at the ripe old age of 122. She smoked cigararettes until age 117, when she finally quit the habit.
Unfortunately, most people will not live so long. In 1800 the average life expectancy was a mere 27 years. By 1900 it was only 47. Although the average life expectancy has nearly doubled in the last hundred years, the majority of us living today will still die sometime in our eighties.
However, there are ...