Philosophers Not Long Life

According to regular rule, philosophers should live a long life. It is because they know human hearts, not could hurt them.
But, almost all of them do not live long for reasons of their own. The following are the name for references.
Socrates ancient Greece, he spent his whole life to find truth of life. He died at age of seventy.
Plate, student of Socrates, he said one famous. Word: “I will write up to my death.” He died at age of eighty.
Aristotle, student of Plate. He is the teacher of King Alexander. He was famous to be father of all knowledge. He died at 62.
Thomas Aquinas, who was the father of God knowledge. He leaded his philosophy into the Christianity. He died at 49.
Rene Descanes, French philosopher, teacher of Queen that time. He was born 1596 died at 1650, living 54 years.