lies to reassure her that he does love her when in fact he does not.

As we read the story, we also discover that Harry is characterised by his desire to be a writer but also by the way that he is struggling to put pen to paper, because of the luxury in which he lives. Note what Harry concludes about how he destroyed his talent:

He had destroyed his talent by not using it, by betrayals of himself and what he believed in, by drinking so much that he blunted the edge of his perceptions, by laziness, by sloth, and by snobbery, by pride and by prejudice, by hook and by crook.

Thus what defines Harry as a character more than anything is his sense of frustration at not being able to write when he has dedicated his life to this purpose. It is thus highly ironic that the short story ends with Harry achieving his goal of artistic transcendence in his death reveries.

Harry, the protagonist of "The Snows of Kilimanjaro," is brutally honest with himself, compassionate and loyal enough to try to protect Helen from his brutal honesty, and a failed writer. 

Dying in Africa from a gangrened leg, Harry doesn't romanticize his life or situation but squarely faces what is: he will die, he's bored with life and death, and he does not love Helen. When she says to him "You're not going to die," he says:

"Don't be silly. I'm dying now. Ask those bastards." He looked over to where the huge, filthy birds [vultures] sat, their naked heads sunk in the hunched feathers.

He thinks of death without denial: 

It came with a rush; not as a rush of water nor of wind; but of a sudden, evil-smelling emptiness and the odd thing was that the hyena slipped lightly along the edge of it.

He admits he's tired of everything:

I'm getting as bored with dying as with everything else, he thought.

He thinks to himself that "he did not love her [Helen] at all," and earlier on he tells Helen this when she asks if he loves her:

"No," said the man. "I don't think so. I never have."

Yet he is compassionate enough to realize he is hurting her, and he wants to spare her, so he says to her:

"I'm crazy as a coot and being as cruel to you as I can be. Don't pay any attention, darling, to what I say. I love you, really. You know I love you. I've never loved any one else the way I love you."

He slipped into the familiar lie he made his bread and butter by.

The final sentence about the "lie" that supported him shows he understands he didn't make it as a writer. Instead, he married a wealthy woman who supported him, lied about loving her, and now is about to die with many of his stories never written:

However you make your living is where your talent lies. He had sold vitality, in one form or another, all his life and when your affections are not too involved you give much better value for the money. He had found that out but he would never write that, now, either. No, he would not write that, although it was well worth writing.

He abandoned his love of writing for comfort and security and now it's too late: he "would not write that."

Harry has been damaged by the war and takes that with him into death. 

Hemingway's protagonist in the story is Harry, a writer facing his death from gangrene, the result of failing to put antiseptic on a scratch on his knee before it became infected. The majority of the story recounts Harry's final hours as he dies on the African plain where he has been on safari with the current rich woman in his life. Harry's conversation with the woman, who is not named, and his life as he remembers and evaluates it reveal his character.

Harry is a sophisticated man, one who has traveled and experienced much of the world. He is cynical, but not insensitive to life--he remembers clearly moments of beauty as well as moments of savage human behavior. His conversations with the woman show that he has the capacity to be cruel. The bitterness with which he approaches his own death spills out in deliberately hurtful, cutting comments to her. Her fear and pain do not move him.

Finally, Harry is brutally honest in assessing how he has compromised his own life, betraying his talent by selling himself to a series of rich women:

He had destroyed his talent himself. Why should he blame this woman because she kept him well? He had destroyed his talent by not using it, by betrayals of himself and what he believed in, by drinking so much that he blunted the edge of his perceptions, by laziness, by sloth, and by snobbery . . . What was his talent anyway? It was a talent all right but instead of using it, he had traded on it. It was never what he had done, but always what he could do. And he had chosen to make his living with something else instead of a pen or a pencil.

As Hemingway depicts him, Harry is perceptive but weak; he dies filled with regret for the choices he has made.

The protagonist of "The Snows of Kilimanjaro" is a lot like Ernest Hemingway himself, so this story is somewhat like a confession. The protagonist has a love for nature, which was also one of Hemingway's outstanding characteristics. From various biographies we learn that Hemingway must have been especially sensitive to visual sensations. The protagonist is fond of adventure. He likes taking risks. He is not squeamish about killing wild animals. He has little sympathy for weakness, including his own. His philosophy would probably include a strong dose of social Darwinism, a belief in survival of the fittest. He likes variety. He gets bored with being in the same place and doing the same things.

"It's a bore," he said out loud.
"What is, my dear?"
"Anything you do too bloody long."

The protagonist has an artistic temperament, in striking contrast to his macho athleticism. The most important thing in his life is his writing. He wants to write even when he is dying. His artistic temperament plus his masculine strength and aggressiveness make him attractive to women. But he is difficult for women to relate to because he needs a lot of time to be alone with his thoughts and his creative writing. (Ralph Waldo Emerson wrote: “Art is a jealous mistress, and if a man has a genius for painting, poetry, music, architecture or philosophy, he makes a bad husband and an ill provider.”) Besides that, the protagonist seems to dislike and fear closeness and sentimentality.  Hemingway himself was married four times. He needed women but couldn’t get along with them. The protagonist, like Hemingway himself, appears to be a heavy drinker.

Harry is a writer who lies dying on the African plain of an infected leg. He is insecure and bitter. He feels that he has not made the best of himself as a writer because he did not take the time to write about things that really mattered to him. He does not like women, especially his wife, and during the story he tries to decide why he married her. He also hates the rich and upper class and unfortunately, his wife was a member of that class. As he takes off in the plane, he realizes he " was going.’’ So he has the plane fly to the summit of Mr. Kilimanjaro in one last attempt at being at the top.