Answer:
The overriding theme of "Just Lather, That's All" is that man is ultimately responsible for his own actions. Although we might often think that we're nothing more than the plaything of irresistible forces beyond our control, in actual fact, we are very much the authors of our own destiny, exercising moral choices at every stage of our lives.
This point is perfectly illustrated by the character of the barber in the story. He may have found himself in a difficult situation, yet he still has the ability to determine his own future. He can cut Captain Torres's throat, which, though it would remove an evil, violent man from the world, would constitute a clear act of murder. Or, he can refrain from killing Torres, a decision he might come to regret in due course.
Either way, the choice is the barber's, and no one else's. Like everyone else in the world, he has to make his own moral choices; no one else can make them for him. When it comes to making such choices, we are effectively all alone in the world. And whatever choices we eventually make, we ultimately have to live with the consequences, as is the case with the barber.
"Just Lather, That's All" presents an existentialist drama of the type explored at length in the plays of Henrik Ibsen compressed into a few pages. The barber has the chance to become a revolutionary hero by killing Captain Torres. He wrestles with his conscience over this opportunity, then decides not to take it. The Captain's final remark, though it provides a neat twist with which to end the story, does not alter any essential aspect of the barber's decision, though it does throw into sharp relief the two very different types of men with whom the story deals.
Captain Torres is a hero and a villain. The barber recognizes that to be a hero to one side is to be a villain to the other. He knows that if he slits Torres's throat while shaving him, he will be denounced as a coward by some, while others would praise him as "The avenger of us all. A name to remember."
In the end, he decides that he will not be a hero or a villain, but a simple barber, who did his work honestly when a man came to him for a shave. The theme of the story is the barber's struggle with his own identity and his final choice of the type of man he wants to be. Though he is not a hero of the revolution, the reader may find some heroism in the simple, honest values by which the barber chooses to define himself.
Explanation: