But subtlety require distinction not vagueness.
Here's a list of ideas that are often confused, but where knowing the difference could make all the difference.
Action vs. Drama
How often have you read a novel opening with an obvious attempt to engage the reader with an action packed sequence, but it completely misses the mark – we don't know the characters involved, we don't know what's at stake.
Good action scenes work because they are dramatic, not because they are action scenes. Action is just spectacle without drama, but drama does very well on its own. If you're wondering how some quiet openings can be so compelling, then it's very likely due to it.
Pleasure vs. Happiness
Just because they can co-exist, does not make them the same. Being high on heroine is very pleasant, but it won't lead to happiness. My grand-parent's generation had happy times during the Blitz, but it can't have been pleasant. You get the idea.
Scene vs. Situation
A situation with dramatic potential does not make a scene – a scene requires that something changes for the character or the story by the end of it. A lovingly detailed situation is just that, until it becomes a scene - make sure it becomes one.
Prudence vs. Prejudice
Is it prudence or prejudice that makes the shop-owner keep his eye on those lads in hoodies by the sweet-counter. Is it ageism or common sense that makes us give the elderly driver a wide berth. Be aware that the character you think is being smart, maybe actually coming across as a bigot.
Love vs. Lust
Can't really avoid this one, and too obvious to need explaining. I hope. Often depicted as two very distinct things, but there's always a little bit of one in the other – how much is down to you.
Are there any other distinctions you think it's essential for a writer to make?