I've previously stated my thoughts on the nature of fear in a discussion about exploration in RPGs here, but because I roll out enough rambling diatribes to gift-wrap my equally massive ego and tie it off in a nice bow, I figured I would restate those thoughts and expand on them further as I study the way I look at player initiative and how to handle pressures.

It is my personal belief that human beings are lazy when they can be and active when they feel they have to be. That's not some kind of cynical 'people are evil' jab, though I think that is the dominant factor in what people consider banal or selfish evil (I can address my perspective on selfishness and how it relates to player ethics another time). Four emotions, being happiness, sorrow, anger, and fear, are generally the most you can reduce human behavior before you start blending distinct things. And since I love neatly compartmentalizing complex systems into easily digestible, clean chunks, let's do that!

Human beings instinctively want to be happy: That is, they want to move to a status quo where they aren't suffering (Sorrow), consistently threatened (Fear), or have to take additional action to get what they want (Anger). Based on this, the logical emotion to follow happiness is actually fear. When people enjoy something, they tend to become jealous of it- keeping it secure and exclusive. The reason 'fear leads to anger' is because that jealousy increasingly does not become enough- their fear turns to sorrow, as the status quo of the object of their jealousy being in peril produces sorrow. The logical progression of each emotion producing the other goes something like this:

1. Happiness (This is fine) -> Fear (This may not be fine) -> Sorrow (This is bad) -> Anger (I will fix this) -> Happiness (This is fine).

Mixing this up creates interesting progressions, but requires a little extra work, especially kicking someone out of their Happiness box.

• Happiness (This is fine) -> Sorrow (Something changed) -> Anger (I will fix this) -> Fear (I will prevent this from happening again) -> Happiness (Done!)
• Happiness (This is fine) -> Anger (I'll make it even better) -> Sorrow (I've made things worse) -> Fear (I can't let things get any worse) -> Anger (At any cost!)

Often (not always) the goal of being a DM is to make the players happy, and this appears to mean making the characters happy. But the characters... shouldn't be constantly happy. The phrase 'fat and happy' appears for a reason. Old King Cole was a merry old soul because he spent his time fiddling rather than fighting. Adventurers spend a lot of time in a state of anger, fixing what they see is wrong with the world. Adventurers can't stay happy, or they stop being adventurers and start becoming sitcom stars.

This is why just pouring on more and more rewards doesn't work- because once you get to a certain level of power, fear stops becoming as much of an issue and sorrow becomes whiny angst. Even in the real world, extremely powerful individuals can be put in life or limb danger and face deep-seated psychological issues. In adventuring power fantasy, those pressures kind of evaporate. The closest problem becomes Superman's 'for the man who has everything' where power comes tied to responsibilitiesThis is very difficult to actually impose, however, so most of the time it becomes squashing the latest annoyance and retiring to a gigamansion.. Just vacillating between anger and happiness or even just degrees of intense anger isn't long-term satisfying, the same way a bag of junk food may be filling, have sufficient calories, and even tasty, but not nutritious. 

While the two ideas don't seem to be related, the exact same trap christened the term 'grimdark'"Grimdark is a subgenre of speculative fiction with a tone, style, or setting that is particularly dystopian, amoral, and violent."
I don't know why, but it seems like British writers are always first in line when it comes to this sort of scenario or setting, followed shortly by Americans and Japanese. Beats me.: Grim, relentless darkness focuses almost entirely on sorrow and anger. Unlimited power fantasy and unlimited crushing pressure are not satisfying because, being two points on a line, they're literally one-dimensional. Even scenarios that focus on three elements and exclude the fourth lack depth, the same way a plane of three points lacks depth. The logical conclusion here is that the best character arcs involve all four emotions. I'll caveat here by saying that sometimes junk food or one-dimensional fun is the right choice, and it's perfectly fine to be fat, happy, and kept in a state of bliss for a period of feel-good, or enjoy the comical/visceral extreme of grimdark bleakness.

What a DM needs to do to maintain player agency is not to press the player characters to feel a specific emotion, but to subtly and logically change the world in such a way that the character they're trying to provoke proceeds to a specific emotional state. When a character feels secure, you need to threaten what they enjoy, but not in a forced way. When a character feels outraged and exhausted, sometimes you need to give them a clean win. When a character feels sorry for themselves or hopeless, you need to give them a reason to act. And when a character is afraid, sooner or later you need to drop the hammer and have their fears be realized in order to validate that fear.

Since this tract was initially started on the basis of 'exploration games', I'm going to make the perhaps shocking assertion that explorers don't generally start at Anger, or even Fear. They start at Sorrow (most characters do, really) and being able to lure characters into a state of sorrow is important to making a game a game about exploration.