This story was told from the point of view of an old man, one of the last of the "old fashioned" earthlings. The "new breed" of Earthling (I forget what the distinction is, but it is supposed to show the earth as more enlightened) is showing around a visiting alien dignitary and they introduce the alien to the old human, as had been rehearsed, (I think) and the human hits the alien with his cane, as a final gesture of defiance. Misguided, perhaps, I can't remember.
The story is The Die-Hard by Alfred Bester.
An old man ("the Old One") is in a hospital. All the evil has been bred out of the human race and the old man is grumbling about how things were better in his day.
'There is no passion, no love, no fear, no death.'
They are waiting for the Galactic Envoy, the first alien visitor. When the alien greets the old man, he hits it with his cane.
'I greet you. I alone can greet you.'
He raised his cane and smote the face with all his strength.
'I'm the last man on earth,' he cried.