The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
So if we've got that torch in an area of otherwise complete darkness, you cannot see the torch at all more than 40' away. Yes, you could rewrite the rules to represent the fact that real world light decreases exponentially with distance and human eyesight has various thresholds of detection. But it's a lot easier just to have options A, B, and C so we don't have to deal with all of that.
Ultimately, the problem with virtually all of these "common sense" interpretations is cherry picking. You're upset that lighting doesn't follow the physical laws surrounding real world illumination but you're just fine with nonsensical notion that I can hit a skilled fighter 10 times with a broadsword and he'll keep on trucking because he's got enough "hit points".
Even on this particular issue, the notion of 'one way' vision isn't very realistic. To even see that torch, it needs to be shedding light on you. So regardless of where you put the range limits, if you can see the torch, the torch can 'see' you. Certainly, it might be more difficult one way, but the light is traveling the entire distance.
The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
So if we've got that torch in an area of otherwise complete darkness, you cannot see the torch at all more than 40' away. Yes, you could rewrite the rules to represent the fact that real world light decreases exponentially with distance and human eyesight has various thresholds of detection. But it's a lot easier just to have options A, B, and C so we don't have to deal with all of that.
That's actually not what the rules say though. The rules say that if you are trying to see an object/creature that is in an area that is Heavily Obscured, such as in darkness, then you have the blinded condition when trying to perceive that object/creature. In this example, the lit torch is NOT in an area of darkness, and thus not in an area that is heavily obscured, and you would not have the blinded condition when trying to perceive it. You could see it clearly, whether you are in an area that is heavily obscured or not.
The thing that stops you from being able to see something while YOU are in an area that is heavily obscured or THROUGH an area that is heavily obscured is NOT found in the rules for "heavily obscured". It's found in the rules for "Line of Sight".
Line of Sight
To determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If you can trace a line that doesn’t pass through or touch an object or effect that blocks vision—such as a stone wall, a thick curtain, or a dense cloud of fog—then there is line of sight.
For the OP, the fog quality of the stinking cloud creates an effect that blocks vision, and thus blocks "Line of Sight". This is also true of a solid objects, dense fog clouds, and dense foliage. That's why you have the blinded condition trying to see something in a fog cloud and trying to see something on the other side of the fog cloud, but you DON'T have the the blinded condition when trying to see something on the other side of an area of darkness. Darkness does not block line of sight. It is not an effect that blocks vision. Fog is. This is exactly why it is absolutely RAW to see a lit torch from over 40 feet away if there is nothing between you and the torch.
The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
So if we've got that torch in an area of otherwise complete darkness, you cannot see the torch at all more than 40' away. Yes, you could rewrite the rules to represent the fact that real world light decreases exponentially with distance and human eyesight has various thresholds of detection. But it's a lot easier just to have options A, B, and C so we don't have to deal with all of that.
That's actually not what the rules say though. The rules say that if you are trying to see an object/creature that is in an area that is Heavily Obscured, such as in darkness, then you have the blinded condition when trying to perceive that object/creature. In this example, the lit torch is NOT in an area of darkness, and thus not in an area that is heavily obscured, and you would not have the blinded condition when trying to perceive it. You could see it clearly, whether you are in an area that is heavily obscured or not.
The thing that stops you from being able to see something while YOU are in an area that is heavily obscured or THROUGH an area that is heavily obscured is NOT found in the rules for "heavily obscured". It's found in the rules for "Line of Sight".
Line of Sight
To determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If you can trace a line that doesn’t pass through or touch an object or effect that blocks vision—such as a stone wall, a thick curtain, or a dense cloud of fog—then there is line of sight.
For the OP, the fog quality of the stinking cloud creates an effect that blocks vision, and thus blocks "Line of Sight". This is also true of a solid objects, dense fog clouds, and dense foliage. That's why you have the blinded condition trying to see something in a fog cloud and trying to see something on the other side of the fog cloud, but you DON'T have the the blinded condition when trying to see something on the other side of an area of darkness. Darkness does not block line of sight. It is not an effect that blocks vision. Fog is. This is exactly why it is absolutely RAW to see a lit torch from over 40 feet away if there is nothing between you and the torch.
Unfortunately, this is not true. In Chapter 1, under vision and light you see both the description of Heavily Obscured areas (which includes Darkness) as "opaque", as well as the condition that Darkness is rather common, even on moonlit nights.
This is definitely a case where RAW gives rather nonsensical results, even in a world of magic... mostly because this Darkness is "mundane", not magical. The fix is quite easy, however, and has been stated already: just allow mundane darkness to be seen through, just not into.
I don't believe the rules are giving nonsensical results. As I pointed out, most of the examples people are using as 'nonsensical' don't involve darkness at all but rather Dimly Lit conditions. So really what people find nonsensical is the specific ranges for light sources (such as those 20/40 ranges for torches). However, this is no more unreasonable than allowing players to stab one another with daggers from 5' away. I'm a pretty big guy, but I don't have 5' arms.
I mean, whether you keep torch distances the same, but allow creatures to see through (the opaque, by rules text) Darkness, or just extend "dim light" to "reasonable ranges", you are effectively doing the same thing: changing the rules to be less nonsensical when it comes to Darkness.
The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
So if we've got that torch in an area of otherwise complete darkness, you cannot see the torch at all more than 40' away. Yes, you could rewrite the rules to represent the fact that real world light decreases exponentially with distance and human eyesight has various thresholds of detection. But it's a lot easier just to have options A, B, and C so we don't have to deal with all of that.
That's actually not what the rules say though. The rules say that if you are trying to see an object/creature that is in an area that is Heavily Obscured, such as in darkness, then you have the blinded condition when trying to perceive that object/creature. In this example, the lit torch is NOT in an area of darkness, and thus not in an area that is heavily obscured, and you would not have the blinded condition when trying to perceive it. You could see it clearly, whether you are in an area that is heavily obscured or not.
The thing that stops you from being able to see something while YOU are in an area that is heavily obscured or THROUGH an area that is heavily obscured is NOT found in the rules for "heavily obscured". It's found in the rules for "Line of Sight".
Line of Sight
To determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If you can trace a line that doesn’t pass through or touch an object or effect that blocks vision—such as a stone wall, a thick curtain, or a dense cloud of fog—then there is line of sight.
For the OP, the fog quality of the stinking cloud creates an effect that blocks vision, and thus blocks "Line of Sight". This is also true of a solid objects, dense fog clouds, and dense foliage. That's why you have the blinded condition trying to see something in a fog cloud and trying to see something on the other side of the fog cloud, but you DON'T have the the blinded condition when trying to see something on the other side of an area of darkness. Darkness does not block line of sight. It is not an effect that blocks vision. Fog is. This is exactly why it is absolutely RAW to see a lit torch from over 40 feet away if there is nothing between you and the torch.
Unfortunately, this is not true. In Chapter 1, under vision and light you see both the description of Heavily Obscured areas (which includes Darkness) as "opaque", as well as the condition that Darkness is rather common, even on moonlit nights.
This is definitely a case where RAW gives rather nonsensical results, even in a world of magic... mostly because this Darkness is "mundane", not magical. The fix is quite easy, however, and has been stated already: just allow mundane darkness to be seen through, just not into.
The word "Opaque" in this case is flavor text, and is not describing the rule. When you look at the Rules Glossary, the ONLY thing it says about Heavily Obscured is "You have the Blinded condition while trying to see something in a Heavily Obscured space." Nothing about opaque, blocking line of sight, etc.
There's a lot in the Basic Rules section that is stated in the Vision and Light section that is obviously descriptive, but not defining/setting a rule. Dim light states "A full moon might bathe the land in Dim Light," but then Darkness states "Characters face Darkness outdoors at night (even most moonlit nights)..."
If we are taking the flavor text as rules, then moonlight nights would be both Dim Light and Darkness, but only maybe Dim Light if the moon is full? But even if the moon is full, it still might be Darkness, because it says "MIGHT bathe...".
Under Hit Points it says "Hit Points represent durability and the will to live." However this doesn't mean that all creatures with Hit Points have a "will to live", does it? Do constructs have a "will to live" because they have Hit Points? Do Animated Objects? Once a creature is brought to 0 Hit Points have they lost all will to live?
There's lots of places in the rules where it gives short, non-exhaustive lists of what can constitute a certain thing, or where it vaguely describes things. But in general those descriptions are meaningless: it is the RULES that come with them that are important. And in this case, the only RULE associated with Heavily Obscured is that you are blinded when trying to see something in there. "Opaque" is the "will to live" of Vision. It doesn't hold any special meaning as a a rule.
If the word "opaque" is flavor with no mechanical meaning, then are we now going to be looking through fog clouds? And where do the rules end and the flavor begin? The line of sight rules look kind of promising, since it doesn't list darkness, except that it lists things the block vision—the very definition of "opaque"—with a non-exhaustive list. And, well, there's no rules glossary definition for LoS, so is that entire thing just flavor text? If not, why not?
Again, we are stuck because we either treat mundane darkness as blocking vision like the other things listed next to the word "opaque" or we treat that as flavor and see through everything that creates Heavily Obscured areas.
And what about magical darkness? Can you see through that? What rules would you quote to make that ruling one way or the other?
As I said in my first post in this thread... We all wish the rules were written the way you describe. They just aren't. Darkness should have specifically been treated differently from fog clouds, but here we are.
For the OP, the fog quality of the stinking cloud creates an effect that blocks vision, and thus blocks "Line of Sight".
The rules say that all heavily obscured areas are opaque, and if we assume not all sources of heavily obscured is opaque, we have no way of knowing which effects are opaque, because the only spells that specifically mention being opaque are spells that create opaque walls, not spells that create heavily obscured areas.
A map location is either Heavily Obscured or not. If it is Heavily Obscured, you cannot trace lines of sight either into or through that area. It's literally that simple.
This is not what the rules actually say. The concept of a Heavily Obscured area is simply that the area itself is such that the things that are located within that area are obscured from view. No reference is made to the concept of Line of Sight, which is a different rule that is found in the DMG.
At any rate, for a stinking cloud, it would be that if you are trying to see things that are within the area that is heavily obscured, you have the blinded condition.
Because it is a cloud of gas, like a fog cloud, if you are within the cloud (within the area that is heavily obscured) you wouldn't be able to see out because the spell creates an effect that blocks sight. So you would be blinded while within the cloud as well.
This is exactly correct! Two different rules apply when dealing with phenomena such as a Stinking Cloud, a Fog Cloud and so on -- the rule for a Heavily Obscured area AND the rule for Line of Sight.
A darkened area where you can see out (without Darkvision) would be considered Dimly Lit and create Lightly Obscured. It would not block line of sight either way.
Non-magical darkness that provides Heavily Obscured is largely confined to dungeons and other indoor areas with no illumination whatsoever. If an area is Heavily Obscured by non-magical darkness, no one can see at all without specialized senses.
Both of these statements are not correct. By rule, Darkness is a Heavily Obscured area. This means that creatures and objects that are located within this Darkness cannot be seen because they are obscured. This has nothing to do with whether or not you can see out of this Darkness to see a nearby campfire. For that, you need to refer to a different rule -- the rule for Line of Sight. Darkness is not a phenomenon that blocks Line of Sight, so there is no reason why you cannot see out of it.
A darkened area where you can see out (without Darkvision) would be considered Dimly Lit and create Lightly Obscured. It would not block line of sight either way.
Um. Let's say you have a 100' long corridor in a dark dungeon, and there's torches (each providing 20' of bright light and another 20' of dim light) at each end. This means there's a 20' segment in the middle of the corridor that is in darkness -- not dimly lit, darkness. Are you asserting that a person in that segment cannot see out? Or that people standing at either end of the corridor cannot see one another?
Now, repeat the thought experiment, except that there is a 10' radius cloud of dense mist in the middle of the corridor.
RAW, this makes absolutely no difference -- in both cases, the center 20' of the corridor is heavily obscured, the rest is either brightly or dimly lit -- but it should be common sense that they are not the same.
RAW treats these two situations completely differently.
In the first case, the person in the Dark area can see out and can view objects that are illuminated by either of the torches just fine, and the people on the ends can see each other, but cannot see the person that is within the Darkness. This is because Darkness is a Heavily Obscured area which obscured the things that are within it from view, but Darkness is not a phenomenon that blocks Line of Sight.
In the second case, the person within the dense mist cloud cannot see out and thus cannot view objects that are illuminated by the torches. The people on the ends cannot see each other and they also cannot see the person that is within the mist. This is because a dense mist cloud is a Heavily Obscured area and it is also a phenomenon that blocks Line of Sight.
The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
A common misconception in this game is that the term "Darkness" actually refers to the total absence of light. It doesn't. There actually IS gradual decline of illumination. But the game divides all possible levels of illumination into one of three categories of illumination, each of which is governed by specific rules. Darkness is simply the darkest category which includes environments such as "most moonlit nights".
Light
The presence or absence of light determines the category of illumination in an area, as defined below.
Characters face Darkness outdoors at night (even most moonlit nights)
under vision and light you see both the description of Heavily Obscured areas (which includes Darkness) as "opaque",
Maximus already did an excellent job explaining the best way to interpret the clause which describes these areas as "opaque", so I won't rehash the entire explanation. I'll just reiterate that this is simply a style of writing that isn't meant to be taken literally in this particular context. Its purpose is to introduce the concept and describe the upcoming rule (which appears in the sentence that follows it) in a manner that compares and contrasts against the mechanic that was previously established under Lightly Obscured areas -- areas where things CAN be seen (with some difficulty).
Here is an example:
"At my church, when giving the homily the priest is transparent. He is open, honest, and easy to understand, with no hidden agendas or secrets."
Then, someone responds to that statement with: "So you're saying that while the priest is giving the homily you can see through the priest and are able to look at objects that are located directly behind him? That doesn't really make sense or fit with the concept that is being described, but I guess I won't really question it . . ."
That's pretty much what is happening here. The word "opaque" has a particular dictionary definition that we are all familiar with. But that's not how the word is being used in this context.
If the word "opaque" is flavor with no mechanical meaning, then are we now going to be looking through fog clouds?
Nope. This was explained quite well earlier by Maximus also. There are two different rules. The rules for Heavily Obscured areas, and the rules for Line of Sight.
If we were to use ONLY the rules for Heavily Obscured areas, then all such areas could be seen out of and seen through, including fog clouds. This is because that rule ONLY addresses the ability to see the things that are located within the area (from anywhere).
However, we should always also be applying the rules for Line of Sight, found in the DMG. Under this rule, the DM determines whether a particular phenomenon blocks Line of Sight or not, and it gives some common examples. But there are many possibilities that would need a ruling on the fly. How about glass? How about stained glass? How about a soap bubble? Thin smoke? Dense smoke? A thin white curtain in full sunlight? Clear water? Murky water? The list is endless. However, it should be pretty universally ruled by most DMs that the phenomenon of Darkness simply does not block Line of Sight. But a fog cloud does. So, because of THIS rule and NOT because of the rule for Heavily Obscured areas, these two phenomena behave differently when it comes to vision mechanics.
And what about magical darkness? Can you see through that? What rules would you quote to make that ruling one way or the other?
As for magical darkness -- the mechanics for such phenomena are determined by the particular effect which creates it. The Darkness that is created by the darkness spell, for example, is governed by slightly different mechanics than the Darkness that is created by some other spells.
In the case of the Darkness spell, an area of mundane Darkness is magically created. Then, the mechanics of this mundane Darkness are magically modified in precisely the ways that are listed in the spell description (and nothing more) -- Non-magical light cannot illuminate it, weak spells which create light are dispelled, and darkvision does not work correctly when trying to see the things that are within the area. Also, it can emanate from and move along with a target object, and such an emanation can be blocked and unblocked as desired. In all other ways, it behaves just like mundane Darkness.
Certain other spells cause creatures located within the magical Darkness to become blinded, for example.
This is exactly correct! Two different rules apply when dealing with phenomena such as a Stinking Cloud, a Fog Cloud and so on -- the rule for a Heavily Obscured area AND the rule for Line of Sight.
There is nothing in the rules that says that stinking cloud blocks line of sight unless that's a generic feature of heavily obscured areas -- it says nothing of the sort in the spell text, and it's not an example given in line of sight.
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The issue with the "common sense" interpretation is that it demands a far more granular approach to lighting than is afforded by the rules. Essentially, you want a rules interpretation where you've got some real number value of illumination that gradually declines from the light source. What the rules actually say is that "we're not going into all that complexity, just use these three discrete values".
So if we've got that torch in an area of otherwise complete darkness, you cannot see the torch at all more than 40' away. Yes, you could rewrite the rules to represent the fact that real world light decreases exponentially with distance and human eyesight has various thresholds of detection. But it's a lot easier just to have options A, B, and C so we don't have to deal with all of that.
Ultimately, the problem with virtually all of these "common sense" interpretations is cherry picking. You're upset that lighting doesn't follow the physical laws surrounding real world illumination but you're just fine with nonsensical notion that I can hit a skilled fighter 10 times with a broadsword and he'll keep on trucking because he's got enough "hit points".
Even on this particular issue, the notion of 'one way' vision isn't very realistic. To even see that torch, it needs to be shedding light on you. So regardless of where you put the range limits, if you can see the torch, the torch can 'see' you. Certainly, it might be more difficult one way, but the light is traveling the entire distance.
No it doesn't. All it demands is changing "darkness" and "heavily obscured" into different conditions.
That's actually not what the rules say though. The rules say that if you are trying to see an object/creature that is in an area that is Heavily Obscured, such as in darkness, then you have the blinded condition when trying to perceive that object/creature. In this example, the lit torch is NOT in an area of darkness, and thus not in an area that is heavily obscured, and you would not have the blinded condition when trying to perceive it. You could see it clearly, whether you are in an area that is heavily obscured or not.
The thing that stops you from being able to see something while YOU are in an area that is heavily obscured or THROUGH an area that is heavily obscured is NOT found in the rules for "heavily obscured". It's found in the rules for "Line of Sight".
For the OP, the fog quality of the stinking cloud creates an effect that blocks vision, and thus blocks "Line of Sight". This is also true of a solid objects, dense fog clouds, and dense foliage. That's why you have the blinded condition trying to see something in a fog cloud and trying to see something on the other side of the fog cloud, but you DON'T have the the blinded condition when trying to see something on the other side of an area of darkness. Darkness does not block line of sight. It is not an effect that blocks vision. Fog is. This is exactly why it is absolutely RAW to see a lit torch from over 40 feet away if there is nothing between you and the torch.
Unfortunately, this is not true. In Chapter 1, under vision and light you see both the description of Heavily Obscured areas (which includes Darkness) as "opaque", as well as the condition that Darkness is rather common, even on moonlit nights.
This is definitely a case where RAW gives rather nonsensical results, even in a world of magic... mostly because this Darkness is "mundane", not magical. The fix is quite easy, however, and has been stated already: just allow mundane darkness to be seen through, just not into.
I don't believe the rules are giving nonsensical results. As I pointed out, most of the examples people are using as 'nonsensical' don't involve darkness at all but rather Dimly Lit conditions. So really what people find nonsensical is the specific ranges for light sources (such as those 20/40 ranges for torches). However, this is no more unreasonable than allowing players to stab one another with daggers from 5' away. I'm a pretty big guy, but I don't have 5' arms.
I mean, whether you keep torch distances the same, but allow creatures to see through (the opaque, by rules text) Darkness, or just extend "dim light" to "reasonable ranges", you are effectively doing the same thing: changing the rules to be less nonsensical when it comes to Darkness.
The word "Opaque" in this case is flavor text, and is not describing the rule. When you look at the Rules Glossary, the ONLY thing it says about Heavily Obscured is "You have the Blinded condition while trying to see something in a Heavily Obscured space." Nothing about opaque, blocking line of sight, etc.
There's a lot in the Basic Rules section that is stated in the Vision and Light section that is obviously descriptive, but not defining/setting a rule. Dim light states "A full moon might bathe the land in Dim Light," but then Darkness states "Characters face Darkness outdoors at night (even most moonlit nights)..."
If we are taking the flavor text as rules, then moonlight nights would be both Dim Light and Darkness, but only maybe Dim Light if the moon is full? But even if the moon is full, it still might be Darkness, because it says "MIGHT bathe...".
Under Hit Points it says "Hit Points represent durability and the will to live." However this doesn't mean that all creatures with Hit Points have a "will to live", does it? Do constructs have a "will to live" because they have Hit Points? Do Animated Objects? Once a creature is brought to 0 Hit Points have they lost all will to live?
There's lots of places in the rules where it gives short, non-exhaustive lists of what can constitute a certain thing, or where it vaguely describes things. But in general those descriptions are meaningless: it is the RULES that come with them that are important. And in this case, the only RULE associated with Heavily Obscured is that you are blinded when trying to see something in there. "Opaque" is the "will to live" of Vision. It doesn't hold any special meaning as a a rule.
I'm pretty sure sure I said something about this before...
I hope the GM isn't confused by the pile of opinions.
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
-Ilyara Thundertale
*sigh*
If the word "opaque" is flavor with no mechanical meaning, then are we now going to be looking through fog clouds? And where do the rules end and the flavor begin? The line of sight rules look kind of promising, since it doesn't list darkness, except that it lists things the block vision—the very definition of "opaque"—with a non-exhaustive list. And, well, there's no rules glossary definition for LoS, so is that entire thing just flavor text? If not, why not?
Again, we are stuck because we either treat mundane darkness as blocking vision like the other things listed next to the word "opaque" or we treat that as flavor and see through everything that creates Heavily Obscured areas.
And what about magical darkness? Can you see through that? What rules would you quote to make that ruling one way or the other?
As I said in my first post in this thread... We all wish the rules were written the way you describe. They just aren't. Darkness should have specifically been treated differently from fog clouds, but here we are.
The rules say that all heavily obscured areas are opaque, and if we assume not all sources of heavily obscured is opaque, we have no way of knowing which effects are opaque, because the only spells that specifically mention being opaque are spells that create opaque walls, not spells that create heavily obscured areas.
It would make the Darkness spell much more effective for infiltration / escape if it didn't create a super obvious bubble of Darkness.
This is not what the rules actually say. The concept of a Heavily Obscured area is simply that the area itself is such that the things that are located within that area are obscured from view. No reference is made to the concept of Line of Sight, which is a different rule that is found in the DMG.
This is exactly correct! Two different rules apply when dealing with phenomena such as a Stinking Cloud, a Fog Cloud and so on -- the rule for a Heavily Obscured area AND the rule for Line of Sight.
Both of these statements are not correct. By rule, Darkness is a Heavily Obscured area. This means that creatures and objects that are located within this Darkness cannot be seen because they are obscured. This has nothing to do with whether or not you can see out of this Darkness to see a nearby campfire. For that, you need to refer to a different rule -- the rule for Line of Sight. Darkness is not a phenomenon that blocks Line of Sight, so there is no reason why you cannot see out of it.
RAW treats these two situations completely differently.
In the first case, the person in the Dark area can see out and can view objects that are illuminated by either of the torches just fine, and the people on the ends can see each other, but cannot see the person that is within the Darkness. This is because Darkness is a Heavily Obscured area which obscured the things that are within it from view, but Darkness is not a phenomenon that blocks Line of Sight.
In the second case, the person within the dense mist cloud cannot see out and thus cannot view objects that are illuminated by the torches. The people on the ends cannot see each other and they also cannot see the person that is within the mist. This is because a dense mist cloud is a Heavily Obscured area and it is also a phenomenon that blocks Line of Sight.
A common misconception in this game is that the term "Darkness" actually refers to the total absence of light. It doesn't. There actually IS gradual decline of illumination. But the game divides all possible levels of illumination into one of three categories of illumination, each of which is governed by specific rules. Darkness is simply the darkest category which includes environments such as "most moonlit nights".
Maximus already did an excellent job explaining the best way to interpret the clause which describes these areas as "opaque", so I won't rehash the entire explanation. I'll just reiterate that this is simply a style of writing that isn't meant to be taken literally in this particular context. Its purpose is to introduce the concept and describe the upcoming rule (which appears in the sentence that follows it) in a manner that compares and contrasts against the mechanic that was previously established under Lightly Obscured areas -- areas where things CAN be seen (with some difficulty).
Here is an example:
"At my church, when giving the homily the priest is transparent. He is open, honest, and easy to understand, with no hidden agendas or secrets."
Then, someone responds to that statement with: "So you're saying that while the priest is giving the homily you can see through the priest and are able to look at objects that are located directly behind him? That doesn't really make sense or fit with the concept that is being described, but I guess I won't really question it . . ."
That's pretty much what is happening here. The word "opaque" has a particular dictionary definition that we are all familiar with. But that's not how the word is being used in this context.
Nope. This was explained quite well earlier by Maximus also. There are two different rules. The rules for Heavily Obscured areas, and the rules for Line of Sight.
If we were to use ONLY the rules for Heavily Obscured areas, then all such areas could be seen out of and seen through, including fog clouds. This is because that rule ONLY addresses the ability to see the things that are located within the area (from anywhere).
However, we should always also be applying the rules for Line of Sight, found in the DMG. Under this rule, the DM determines whether a particular phenomenon blocks Line of Sight or not, and it gives some common examples. But there are many possibilities that would need a ruling on the fly. How about glass? How about stained glass? How about a soap bubble? Thin smoke? Dense smoke? A thin white curtain in full sunlight? Clear water? Murky water? The list is endless. However, it should be pretty universally ruled by most DMs that the phenomenon of Darkness simply does not block Line of Sight. But a fog cloud does. So, because of THIS rule and NOT because of the rule for Heavily Obscured areas, these two phenomena behave differently when it comes to vision mechanics.
As for magical darkness -- the mechanics for such phenomena are determined by the particular effect which creates it. The Darkness that is created by the darkness spell, for example, is governed by slightly different mechanics than the Darkness that is created by some other spells.
In the case of the Darkness spell, an area of mundane Darkness is magically created. Then, the mechanics of this mundane Darkness are magically modified in precisely the ways that are listed in the spell description (and nothing more) -- Non-magical light cannot illuminate it, weak spells which create light are dispelled, and darkvision does not work correctly when trying to see the things that are within the area. Also, it can emanate from and move along with a target object, and such an emanation can be blocked and unblocked as desired. In all other ways, it behaves just like mundane Darkness.
Certain other spells cause creatures located within the magical Darkness to become blinded, for example.
There is nothing in the rules that says that stinking cloud blocks line of sight unless that's a generic feature of heavily obscured areas -- it says nothing of the sort in the spell text, and it's not an example given in line of sight.