Was the story of "Young Goodman Brown" a dream or reality for Brown?

The events that take place in this short story might have been a dream, but they certainly do not feel that way to young Goodman Brown himself. After Brown begs Faith, his wife, to resist the devil, he finds himself all alone in the dark forest. He returns to the village, a changed man from the one he was just the evening before, and the narrator asks,

Had Goodman Brown fallen asleep in the forest, and only dreamed a wild dream of a witch-meeting? Be it so, if you will.

We, the readers, can tell ourselves that it was a dream if we prefer, but Goodman Brown does not seem to think of his experiences as a dream. He acts as though he believes that the events took place in reality. "A stern, a sad, a darkly meditative, a distrustful, if not a desperate man, did he become [...]." When Brown sees Goody Cloyse with a little girl, he "snatched away the child, as from the grasp of the fiend himself." He cannot even take comfort in Faith, his wife. Then, "On the Sabbath-day, when the congregation were singing a holy psalm, he could not listen, because an anthem of sin rushed loudly upon his ear, and drowned all the blessed strain." Brown spends the remainder of his life in "gloom," unable to trust, or have faith, in anyone or anything. If Brown believed he'd only had a dream, it seems unlikely that he would be so irrevocably altered.

Is Brown's experience in "Young Goodman Brown" a dream or reality, and does its nature matter?

I edited your post down to this essential question because you are only allowed to ask one question at a time. 

Your second question is Hawthorne's whole point.  Whether Goodman Brown's experience in the woods was real or not absolutely does not matter.  Brown is forever changed by whatever it is he experienced that night -- dream or real.  Brown, like all human beings, is questioning the good and evil of his fellow man.  Once he sees people he assumed where good at a witch meeting with the Devil, he realizes that there is the potential for sin in everyone.  He assumes Faith is full of faith, but when he sees her pink ribbons in the woods, he realizes that even she is tempted by evil.  Once he comes to this realization, he can't come to any fair perspective on the issue.  He sees only the bad in people, discounting any of the good he saw before.  This knowledge turns him into a bitter and angry man who destroys his happiness and his faith in humanity.  The ultimate irony of the story is that the Devil's promised gift to the members of the meeting is the ability to see into the evil of man's secret heart.  Goodman Brown rejects the Devil's deal and "saves himself," but he still seems to end up with the knowledge, and that knowledge makes him a miserable person. 

How do imagination and reality interact in "Young Goodman Brown"?

There is an ambiguity within "Young Goodman Brown" as to whether his vision in the forest actually happened to him, or whether it was a dream. The story does not express a clear answer to this question either way.

As far as this question is concerned, however, it might be useful to consider the story's resolution, rather than the vision in the forest (because there, that ambiguity between imagination and reality does not exist, and one can more clearly discern the ways through which the one influences the other).

Goodman Brown's vision in the forest has destroyed his capacity to trust in the goodness of others. From that point on, he can only see wickedness and sin around him. This we see in his return to Salem and his treatment of the people there. When the minister gives him a blessing, he recoils from it. Meanwhile, Hawthorne writes of his encounter with Goody Cloyse:

Goody Cloyse, that excellent old Christian, stood in the early sunshine at her own lattice, catechizing a little girl who had brought her a pint of morning's milk. Goodman Brown snatched away the child as from the grasp of the fiend himself.

Finally, there is his reunion with his wife, Faith, who meets him joyfully. Hawthorne writes of his response:

Goodman Brown looked sternly and sadly into her face, and passed on without a greeting.

From the beginning of the story, Goodman Brown's expectations of the people around him have shaped his perception of the world. This is a factor which would continue to hold true at its end. After his vision in the forest, Brown has become a cynic, and those cynical expectations will proceed to shape his perception of reality. The result is to cast the remainder of his life in misery.

How do imagination and reality interact in "Young Goodman Brown"?

Nathaniel Hawthorne's story is precisely about the relationship between imagination and reality. Goodman Brown may have a powerful imagination, or strange things may have happened to him in the forest. It is also possible that these strange things happen to him precisely because he is sensitive to supernatural forces (through his imagination) that less sensitive people would not notice; that is, Goodman is a visionary.

Hawthorne may be telling a story about one person and his walk through the woods. He may also be relating an allegory of a spiritual journey that includes temptation and resistance. Goodman's name is a hint toward that interpretation. More broadly, this one man's story can be understood as standing for the larger Puritan community of which he is a part. Rather than emphasizing Brown as an individual, the reader can think about characteristics of a Puritan outlook on such concepts as sin and possession and consequently their powerful influence on the way in which people see the world.

How do imagination and reality interact in "Young Goodman Brown"?

In one of Dean Kootz's novels, a character declares that "perception is reality" and in the case of the character Young Goodman Brown this is certainly true. A proud, sanctimonious character, who fancies himself as the only one capable of journeying with the devil and being able to return with his soul unscathed, Goodman perceives everyone in relation to his self-image. With this sanctimonious self-deception, Goodman Brown's imagination interprets events into his own reality.

Was everything in "Young Goodman Brown" real or imaginary?

Even though Hawthorne leaves the interpretation of Goodman Brown's experience up to the reader, there are various elements that suggest Brown's experience was indeed imaginary. The magical nature of the enigmatic fellow traveler's staff, the ominous black cloud that follows Brown through the forest, the diverse congregation participating in the Black Mass, and the sudden disappearance of the deacon, minister, and Goody Cloyse suggest that Brown's experience was imaginary. The fact that Brown also uses the traveler's staff to fly through the forest to participate in the Black Mass, where Faith is suddenly present, also suggests that his experience was imaginary.

Regardless of whether Brown's experience was real or imaginary, the outcome of his loss of faith negatively impacts the remainder of Brown's life. After waking up in the forest, Brown becomes suspicious of his community's religious leaders and recognizes them has debased hypocrites who hide their sins and attempt to conceal their wicked actions. Brown lives the remainder of his life as a distant, cynical man who has abandoned all hope and faith in humanity. Through Brown's experience, Hawthorne comments on the nature of faith, religious hypocrisy, loss of innocence, and humanity's inherent nature.

Was everything in "Young Goodman Brown" real or imaginary?

The short answer is that we don't really know whether what Goodman Brown saw was real or if he simply imagined it. At the witches' meeting, he tells his wife, Faith, to resist the Devil, but 

Whether Faith obeyed, he knew not. Hardly had he spoken, when he found himself amid calm night and solitude, listening to a roar of the wind, which died heavily away through the forest. . . .  Had Goodman Brown fallen asleep in the forest, and only dreamed a wild dream of a witch-meeting? Be it so, if you will.

As soon as he tells Faith to resist, the fiery and fiendish scene around him disappears, and Brown stands in the cool, calm forest alone. The narrator says that we are free to believe that Brown had only fallen asleep and dreamed everything he saw. But why? Doesn't it matter whether or not it was real?

Brown lives the remainder of his life as though it were real, as though all of it did really happen. When he sees Faith, happy to see him, he "looked sternly and sadly into her face, and passed on without a greeting." He became a "stern, a sad, a darkly meditative, a distrustful, if not a desperate man . . . from the night of that fearful dream." He cannot stand to hear the congregation sing, to listen to the minister preach. He even "shrank from the bosom of Faith." In other words, he has lost his religious faith. Brown can no longer find solace in the faith he had assumed would simply be there waiting for him to pick up again after his one last night of sin. He had turned his back on God even before he met the Devil in the forest. He had thought to himself: "after this one night, I'll cling to [Faith's] skirts and follow her to Heaven." However, this is not how faith works; one must work, actively and constantly, to abide by God's laws—one cannot simply decide to ignore them one moment and then resume them the next. What Brown saw or did not see in the forest is not important. What is important is that he decided to go into the forest, for some dark intent, in the first place.

In "Young Goodman Brown," was Brown's forest experience a dream or reality?

Hawthorne's tales inhabit a middle ground between illusion and reality. The reader often cannot be sure if the action is presented as something actually occurring, if it is a dream or hallucinatory experience, or if it is somehow all of the above. This ambiguity is a central theme of Romantic (especially Dark Romantic) literature, and it is an extension of the nineteenth-century view of man as a being who essentially creates a reality of his own through the power of his mind. As in the stories of Edgar Allan Poe, one of Hawthorne's contemporaries, there is no simple answer to the question of dream vs. reality in "Young Goodman Brown."

Hawthorne's personal religious beliefs are open to interpretation, but by his time, even most devout Christians probably no longer believed that Satan or the Devil was an actual being who took human form and visited people on earth. The story of Goodman Brown meeting the mysterious stranger in the woods is a parable, a metaphorical representation of the struggle within one man's soul. The Devil "wins," not because he is converting Brown into an evil man, but because Brown turns into a misanthrope, hating and distrusting other human beings (including his wife, Faith) on account of their supposed evil.

Hawthorne himself asks the following question:

Had Goodman Brown fallen asleep in the forest, and only dreamed a wild dream of a witch-meeting? Be it so, if you will. But, alas! it was a dream of evil omen for young Goodman Brown.

That the question is left open is typical of Hawthorne, Poe, and other writers of their period.

In "Young Goodman Brown," was Brown's forest experience a dream or reality?

The answer to this question can be left to the opinions of individual readers. The narrator of the story does not tell readers either way if Brown's experience in the forest was dream or reality. It definitely could have been a reality. Brown certainly thought so; however, if a reader absolutely doesn't believe in Satan, then that reader can also defend the position that it was a dream. Certainly, it seems quite fantastical that all of those seemingly good people could be servants of the Devil, but then again, the Devil is a powerful being. I don't think it truly matters if it is real or not. The result is the same. Brown is left a shell of a man. He has lost his faith in his religion, in his wife, and in his fellow townspeople. After seeing what Brown saw, he simply can't bring himself to interact with anybody in the way that he used to interact. This is probably why I would side with the events being real. I've had some vivid and very real feeling dreams; however, I always realized it was a dream shortly after waking up.

Does "Young Goodman Brown" contain elements of fantasy?

This is a very pertinent question, because the truth of the matter is that Hawthorne manages to create a real sense of ambiguity over the travels of Goodman Brown into the woods. We are never really sure what is real and what is fantasy, just a dream that he had, and the way in which the narrator himself asks this serves to make us unsure of deciding either way. Note the rhetorical question that is asked at the end of the story:

Had Goodman Brown fallen asleep in th forest, and only dreamed a wild dream of a witch-meeting?

So, it is very hard for us to distinguish fact from fiction in this tale. Having said this though, there are definitely elements of fantasy in the account that we are given of what happened. Certainly, one place to start would be with the gentleman that accompanies Goodman Brown and the way that his staff is described:

But the only thing about him that could be fixed upon as remarkable was his staff, which bore the likeness of a grat black snake, so curiously wrought that it might almost be seen to twist and wriggle itself like a living serpent.

Note how later on this staff is suggested to have transformed itself into a snake when the gentleman throws it to Goody Cloyse. In addition, you might like to look at how the meeting is described that Goodman Brown spies upon, and in particular the "music" he hears coming from it as he approaches:

The verse died heavily away, and was lengthened by a chors, not of human voices, but of all the sounds of the benighted wilderness pealing in awful harmony together.

Such accounts obviously add a fantastical element to the tale, but, as I previously mentioned, we are never able to prove that Goodman Brown's adventure in the woods happened factually or whether it was just a dream.

What is the relationship between imagination and reality in "Young Goodman Brown"?

The supposedly-imagined dream of YGB in which he saw a witches Sabbath, the baptism into the "mystery of sin", the evil man, and all the other rituals, had a real effect on him as a person both physically, psychologically, socially, and most importantly spiritually.  An event which supposedly takes place in the mind can in fact effect a person to the point of physical danger which is the whole idea behind YGB: That the sins of the mind and the sins of the soul, though abstract, can cause concrete effects in all humans the way that sin can endanger and affect our bodies through poisoning our minds and souls.

To answer concisely, it is the combination of the visible and the invisible working together concretely which makes the imaginary and the real have a working relationship.

Did Goodman Brown dream most of what happened in the woods in "Young Goodman Brown"?

This is a much-asked question concerning this short story, as Hawthorne deliberately leaves it unspecified as to whether Goodman Brown dreams what he sees as he takes his walk into the woods, or whether it was actually something that really occurred. The sudden way in which Goodman Brown is shifted from a scene where he is imploring his wife, Faith, to remain true to God and then is alone by himself in the woods, "amid calm night and solitude," only able to listen to the noise of the wind as it dies down in the woods, either suggests a very strong dream or magic of some description.

However, it is clear that Hawthorne's focus was not on whether the events actually occurred or not: his intention was to show the impact that Goodman Brown's vision of the evil within all humanity has on him, and how it turns him into a rather bitter and depressing individual. Note that when the narrator asks precisely this question, he responds that "if you will" it to be a dream you can, but:

...it was a dream of evil omen for young Goodman Brown. A stern, a sad, a darkly meditative, a distrustful, if not a desperate man did he become from the night of that fearful dream.

Dream or reality in a sense does not really matter. What does matter is the way that this night changed Goodman Brown for the worse and how it impacted the rest of his life. The importance of what Goodman Brown lies not in whether it was a dream or reality, but the truth that it showed him about the capacity within us all to commit evil acts, no matter how "good" we may ostensibly be.

Are the events in "Young Goodman Brown" all a dream?

Since Young Goodman Brown is a very symbolic story and nearly everything from the main characters' names all the way to phrases are allegorical, I am inclined to think that the author did intend for it to be "real enough" to create a cause and effect in the character and, at the same time, to teach the reader a lesson on conscience and morals.

I think Young Goodman Brown had an encounter with something evil that summoned his backbone to the core, and everything about life as he knew it made him realize that he was indeed a less "good man" than he (or us) would imagine him to be, despite of the squeaky clean first impression we get.

Another possibility is that he had a supernatural encounter which was also true and in the midst of it all it came down to reside within his subconscious forever.

Are the events in "Young Goodman Brown" all a dream?

From the context of the story, there is no definitive way to tell whether or not the events in the forest are a dream. 

Had goodman Brown fallen asleep in the forest, and only dreamed a wild dream of a witch-meeting? 

Be it so, if you will. But, alas! it was a dream of evil omen for a young goodman Brown. 

"Be it so, if you will." This implies that it is open to interpretation. The reader must answer the question. Was it a dream? "Be it so, if you (reader) will." It is quite persuasive that it is a dream, based on the following line: 

A stern, a sad, a darkly meditative, a distrustful, if not a desperate man, did he become, from the night of that fearful dream. 

However, whether it is in the form of a dream or in reality, what Brown "sees" is the potential for evil in the world. That is, he "sees" this evil in reality or as a vision/dream. It is irrelevant whether it comes in the form of dream or reality. The significant thing is that Brown "sees" the potential for evil. 

There are other indications in the story that illustrate the fine line between dream and reality. In the opening paragraphs, Brown comments on Faith and how dreams influence reality: 

'What a wretch am I, to leave her on such an errand! She talks of dreams, too. Methought, as she she spoke, there was trouble in her face, as if a dream had warned her what work is to be done to-night. 

One of the aspects of this story is that dreams, visions, and intuitions can influence reality and vice versa. In fact, a dream might reflect something about reality. In that case, even if the journey through forest is a dream, it might reflect an aspect of reality or it might suppose something that is yet to be. Whether or not it is a dream is irrelevant because Brown would interpret the same thing from either: a revelation, notably a very pessimistic one, about evil. 

What aspects of "Young Goodman Brown" are realistic or fantastical, and can they coexist?

Goodman Brown’s experience in the forest–whether dream or reality–causes him to lose his faith in others and die an unhappy man. Note the last words of the story: “They carved no hopeful verse upon his tombstone; for his dying hour was gloom.”  
 

 Goodman Brown discovers that even highly respected people in Salem fall victim to the forces of darkness. Today–when corporate executives cheat stockholders, politicians lie to win elections, and members of the clergy defraud their congregations–this theme still resonates.  “There is no good on earth,” Goodman Brown observes, “and sin is but a name.” In other words, whether an action is good or evil appears to depend on who is viewing the action.There are, of course, absolute moral values which should prevail for everyone, regardless of their religion or lack of it. For example, murder is always wrong; child abuse is always wrong. However, the devil figure succeeds in confounding Brown on what is truly right and what is truly wrong. 

Hawthorne leaves open to question whether Goodman Brown’s experience is real or imagined, as in a dream. Keep in mind that normal, mentally stable people–like you or those around you–sometimes accept delusions, fantasies, or fabrications as real events. Keep in mind, too, that they sometimes see evil in a person who has done no evil. 

Was everything Brown witnessed in "Young Goodman Brown" a dream or his imagination?

I can only suggest that it is irrelevant; the effect on Brown of what happened is all that matters. Much like Brown, we all must take a journey "into the woods"; we all must learn that everyone is made up of some good or some evil. How we deal with that knowledge is what is important. Brown can not (or choses not to) deal with what he learns. He wants people on his terms; he has developed a certain expectation of his catechism teacher, his pastor, his wife, and that is the way that he will take them ... no other.

This is a recurring theme in Hawthorne. If you have read "The Scarlet Letter," you know that all of the characters have some good and some evil in them, that they (we) are all complex characters. The society of TSL, much like Brown, fails to accept this and punishes only one aspect of a person. Even the threat of this punishment wrecks Arthur's life.

This theme of accepting only the perfect, and its destructive effects on individuals appears in many other Hawthorne works: "The Birthmark," and "The Minister's Black Veil" are other examples you might want to pursue.

"The enemy of the good is the perfect."

Was everything Brown witnessed in "Young Goodman Brown" a dream or his imagination?

There is not a definitive answer to your question! The ending of the story was purposely left ambiguous. It is up to the reader to decide if it was all just a dream or if it really happened.

What is clear is that Brown was changed by the dream/event and became an embittered man. He died an unhappy and untrusting person. This is a sharp contrast to the happy and confidant man that took went on a walk with a stranger.