Estimates of the number of human beings who have ever lived vary greatly and are hotly contested, but many of the estimates range from 90 to 110 billion. With a world population of 6.6 billion in September 2007, it would be a reasonable guess to say that about 6 or 7 per cent of the people who have ever lived are alive today.
What they said:
“A teacher affects eternity. he can never tell where his influence stops.” - Henry Brooks Adams, author.