The Value of a Person

"Everybody can be great.  Because anybody can serve.  You don't have to have a college degree to serve.  You don't have to make your subject and your verb to agree to serve.  You don't have to know about Plato and Aristotle to serve.  You don't have to know Einstein's theory of relativity to serve.  You don't have to know the second law of thermodynamics in Physics to serve.  You only need a heart full of grace; a soul generated by love."

Martin Luther King, quoted in "The Words of Martin Luther King"

This is quite a challenging quotation from Martin Luther King.  What does he mean by "serve"?  What point is he trying to make about the way in which we live our lives?