literal one, but it’s still a vision all the same, and it has transformed Robert's life accordingly.

The act of drawing and the powerful effect it has on Robert bear eloquent testimony to the transformative nature of art. Art can truly change people’s lives, broadening their horizons, giving them a privileged insight into a whole different reality. And that’s what’s happening here.

Robert wants to share his experience with the narrator, who despite being sighted, is initially blind to the cathedral’s cultural, spiritual, and aesthetic significance. It’s only when he draws a picture of the cathedral with Robert that he’s finally able to get a glimpse of a world outside his own, a world that’s freighted with much deeper significance than the one in which he normally lives.

In spiritual and aesthetic terms, the narrator had been blind. But now thanks to the literally blind Robert, he has experienced a truly life-changing vision, a vision symbolized by the cathedral.

In Raymond Carver's "Cathedral," the church building symbolizes  vision to the narrator. Vision is...

...an experience in which a [person], thing, or event appears vividly or credibly to the mind, although not actually present.

The blind man's eyes do not "work," but he "sees" so much more than the narrator whose sight is not impaired—though his perceptions of the world seem to be. The narrator has a limited understanding of the world: he makes judgments based on what he sees. Robert, the blind man, bases his perceptions on what he feels within: he may not see the cathedral, but to him it symbolizes learning—its grandeur is not what makes it important, but the work of countless men who lived and died to build the structure without ever having the satisfaction of seeing it completed in their lifetime. 

The narrator lets his jealousy of the platonic relationship his wife shares with Robert, over many years of acquaintance and the death of his wife, interfere with the narrator's ability to behave like an adult. As they prepare for Robert's arrival, the narrator 'snidely suggests how he might entertain the man.

Maybe I could take him bowling... 

His wife makes it clear that if their relationship means anything to him, he will be nice to this man who is not only her friend, but who has recently lost his wife.

Their conversation provides indirect characterization: when he notes he has no blind friends, his wife points out he has no friends at all. We learn that he is a shallow individual. When he behaves ignorantly again, she begins to lose patience with him:

She'd told me a little about the blind man's wife. Her name was Beulah. Beulah! That's a name for a colored woman. 

"Was his wife a Negro?" I asked.

"Are you crazy?" my wife said. "Have you just flipped or something?...What's wrong with you?" she said. "Are you drunk?"

His tendency to generalize can be seen in his question about Robert's dead wife: that Beulah was "a name for a colored woman." By the time Robert arrives, the narrator has shown how insensitive he is; his wife is disgusted with him.

As the evening progresses, the narrator learns that what he thought he knew of the blind (very little) is untrue: he'd heard they didn't smoke because they could not see the smoke they exhaled—Robert smokes...a lot. Robert decides to "watch" TV with the narrator, who says he is happy to have the company...and means it—showing a subtle shift in his character. The program is about cathedrals, and he asks Robert what he knows about them. Robert says:

I know generations of the same families worked on a cathedral...The men who began their life's work on them, they never lived to see the completion of their work...they're no different from the rest of us, right?

It is not a surprise when the host admits he believes in nothing. Then Robert asks him to draw a cathedral—eyes opened at first and then closed—while Robert follows the movement of his hand. The host is transported. Robert asks him to look, but he hesitates, and...

I didn't feel like I was inside anything.

The narrator has an epiphany—"a sudden intuitive realization." He understands the world without sight. It changes his sense of what he thinks he knows—no longer judging by appearance or preconceptions, but experiencing the world through his "mind's eye." A cathedral is awe-inspiring visually, but the host is inspired because he "feels" it, and so, knows it as well. 

In Raymond Carver's short story "Cathedral," the narrator's narrow-mindedness at the start of the story functions as his metaphorical blindness to the lives of others that are different from his own. Ironically, it is a bonding experience with a blind man named Robert that reveals to the narrator his own figurative inability to see the world in as full and rich a manner as Richard sees it. Thanks to Robert, the narrator's eyes are opened to the possibilities of a beautiful and interesting life outside the realms of what the narrator previously thought possible.

By exploring the theme of blindness in this way, Carver exposes the reader to his or her own possible experiences with figurative blindness, or rather, closed-mindedness. Carver takes a reasonable anxiety around a new experience (meeting a blind man for the first time) and explores the anxiety as well as the remedy with simplicity, sensitivity, and detail. In this way, Carver not only reveals the character of the anxious narrator and Robert, the blind man, but also the character of the reader, who cannot help but ask him or herself how he or she would feel if placed in a similar situation as the narrator.

In this story, the blind man is the one who can truly "see", or who really understands how life can be beautiful, meaningful, and happy, whereas the narrator is the one who is "blind" to those things.  The narrator spends the entire time moaning and groaning about life, his wife, the blind man, and his station in life, and it isn't until the very end, when he closes his eyes and guides the blind man's hands, that he truly sees and feels a profound experience that makes him grateful and happy.  The narrator, a very sarcastic and bitter man, feels, as he closes his eyes to attempt to draw a cathedral for a blind man, that "it was like nothing else in my life up to now."  That's a pretty strong statement for him, considering how negative he's been in the story up to this point.  He has to let go of the senses that he has clung to for so long, and in the dark, have a leap of faith as he drew the cathedral.  He put himself in someone else's shoes, something that he probably has never even tried before.  Before this, he was a bit resentful of the blind man coming to visit, resentful of the company, his wife's fondness for the man, and the inconvenience the visit put on his life.  He was thinking only from his own perspective-not from the blind man's, or his wife's.  But, as he closes his eyes and draws, he sees life from another person's perspective, and finds it incredible.  It is a profound moment for him.  So, the blind man led the seeing man to truly see something for the first time in his life.  The blind man reveals the petty, selfish nature of the narrator, and then helps him to have an experience that will hopefully help to change that character.  Blindness helps to reveal Robert as the truly seeing, wise one, that guides the storyteller to new and positive experiences.

Those are just some thoughts along those lines; I hope that they help get you started.  Good luck!

This is a great question. Of course, there is a massive irony in this story. Robert, the blind man that your question refers to, although he does lack vision, ironically shows that he "sees" far more than any other character. Consider his empathy and understanding that he displays towards both the narrator and the narrator's wife. Although the narrator is extremely rude to him, he does not respond in kind, but shows immense sensitivity and kindness towards both the narrator and his wife.

However, at the end of the story in particular, when he and the narrator draw a cathedral together, Robert manages to help the narrator himself to widen his vision and to see things differently, drawing a cathedral so Robert can "see" what one looks like. The final irony of the story is that the narrator himself closes his eyes too, so that he can "see" better too. Robert has helped the narrator to get in touch with his imagination and creativity by drawing the cathedral, in the same way that Robert's relationship with the narrator's wife inspired her to write poetry. The narrator feels "connected" to Robert, and the impact of this is profoundly liberating:

My eyes were still closed. I was in my house. I knew that. But I didn't feel like I was inside anything.

"It's really something," I said.

Robert is literally blind, and it is the narrator who is figuratively blind because it is not until he closes his eyes and draws with Robert that he can begin to perceive. 

A man who remains closed, the narrator is uncomfortable with the thought of his wife's old friend Robert's upcoming visit. When he comments on this odd friendship, she rejoins that he has no friends, strange or otherwise. Because his wife has communicated much of her personal life to this man, the narrator feels uneasy about the man's meeting him as it places the narrator in what he feels is a vulnerable position since his life has been bared, but Robert's is unknown to him. His wife once asked if he would like to hear a tape from her friend, as this is the method by which they communicate. When she puts the tape on and plays it, the narrator recalls,

After a few minutes of harmless chitchat, I heard my own name in the mouth of this stranger, this blind man I didn't even know. And then this: "From all you've said about him, I can only conclude--" But we were interrupted...it was just as well. I'd heard all I wanted to.

Besides feeling compromised by a stranger knowing so much about him, the narrator holds a disparaging attitude toward this sightless man that demonstrates his narrow-mindedness. For one thing, he feels that the man's wife was deprived by her husband's inability to see her since he could never compliment her looks, or

receive the smallest compliment from her husband. A woman whose husband could never read the expression on her face...Pathetic.

When Robert arrives, the narrator is at a loss for words as he thinks about mentioning the scenic view to their house, but stops himself. Robert, however, is friendly and, to the narrator's displeasure, tells him he feels as though he knows the husband already. Ill at ease, the narrator makes drinks and has a few himself. As he watches Robert, the narrator is surprised that Robert smokes, and he is amazed at how deft Robert is with his knife and fork at dinner. After dinner, they move to the living room and the wife and Robert converse at length.

More talk of Robert....[he] had done a little of everything....He talked in his loud voice about conversations he'd had in Guam, in the Philippines, in Alaska, and even in Tahiti. He said he'd have a lot of friends there if he ever wanted to go visit...

When the narrator feels that Robert has, perhaps, "run down," he turns on the television, but he notices that his wife glares at him with irritation. Then, she turns to Robert and asks him if he has a TV; Robert replies that he has two of them. "I had absolutely nothing to say to that. No opinion," the narrator comments. Shortly, the wife leaves the room and the narrator is alone with Robert. He asks his wife's guest if he would like another drink and Robert says yes. Then, the narrator asks if he would like "to smoke some dope" with him. Robert replies that he will try it. "That's the stuff," the narrator says.

Having returned, his wife gives the narrator "a savage look" for his behavior. She apologizes for her fatigue, and tells Robert that his room is ready, but he replies that he is not tired. It is not long before she falls asleep. The narrator confides that he rarely goes to bed when his wife does because if he does he has "crazy dreams." Tonight, also, the narrator feels inhibited; however, as Robert listens to the television on which an Englishman speaks of the medieval cathedrals, the narrator asks Robert if he knows what a cathedral is. Never ill at ease, Robert asks him to describe one; however, the narrator regrets that he really cannot. So, Robert asks him to draw it for him and places his hand over that of the narrator. 

So we kept on with it. His fingers rode my fingers as my hand went over the paper. It was like nothing else in my life up to now.

Relaxed from the drink and the cannabis, the narrator feels the warmth of friendship. When Robert asks him how the cathedral looks, the narrator can only express his communion with Robert by remarking, "It's really something." This blind man whose heart is open opens the narrator's heart so that he can see what is truly meaningful in life. Robert "sees" how to get along with others and loses his feelings of alienation as his warm hand follows the lines drawn by the narrator, and the narrator feels "really something" in the warmth which Robert extends to him.

In "Cathedral," Raymond Carver reflects on what it really means to be blind. One character is physically blind, yet this man actually has significant insight into life and reality. The narrator has his physical sight, but he is metaphorically blind in many ways.

The narrator, for instance, carries many prejudices about people. He has no idea what it is to be blind and knows about blind people only from what he has seen in movies. What's more, he is jealous of the friendship between the blind man and his wife, who have known each other for a long time. He even supposes that the blind man's wife must have been Black because her name was Beulah.

The narrator holds to no sort of religious beliefs either. In fact, he tells the blind man that he doesn't believe in anything at all. Indeed, the narrator's view of reality and of other people is pretty dim at best and often completely blinded by his own presuppositions.

Ironically, it is the blind man who helps the narrator begin to overcome his blindness. After the narrator's wife goes to bed, the narrator and the blind man turn their attention to a television program about medieval cathedrals. The blind man cannot fully understand what a cathedral is, so together, the narrator and the man draw a cathedral, with the blind man following the narrator's hand. The narrator closes his eyes, finally trying to see what life must be like without physical sight. In the process, he gains some sight of his own.