(CBS News) I have been a working reporter for more than half a century, and the other day someone asked me what all those years had taught me.
What I've learned, I think, and am convinced, is there are four powerful forces in the world, and human events come down to which one prevails.
Those forces are love, knowledge, ignorance and hate.
There is no more powerful force than love -- a parent's love for a child may be the most powerful force of human nature.
Yet hate is also powerful, and has always been with us. I have never quite come to terms with how Hitler could have come to power, not hundreds of years ago but in my lifetime. How did civilized people let that happen?
What I do know is that hate is the product of ignorance and intolerance. Love is strengthened by knowledge.
On this weekend, which is a time of reflection for so many on the purpose of life, I recall what the historian Will Durant once wrote: "Barbarism, like the jungle, does not die, but only retreats behind the barriers that civilization has thrown up against it, and waits there always to reclaim that which civilization has taken from it."
Knowledge, tolerance and understanding are civilization's barriers, and they remain in place only so long as the forces of good are there to maintain them.