"He copied me:" Plagiarism, or coincidence?

This post is to address something that I'm surprised hasn't come up yet: accusations of copying other people's arcs.

We all know there are only so many basic stories, everything else is just variations on a theme. Also, certain plots fall into the category of "I can't believe the devs haven't done that yet," especially when dealing with canon groups. So where's the line?

Where does "this arc has similarities to that guy's arc" become "this arc looks like a ripoff of that guy's arc"? How close is too close? Is anything with a basis, however tenuous, in canon occurrences, however obscure, fair game? Or is everything fair game?

Note that I am not referring to the deliberate copying of someone else's work, in any form. I'm just asking, if you have an idea, and someone else had the same basic idea, but wrote and published an arc about it first, should you bother with yours?

---

Eva Destruction AR/Fire/Munitions Blaster
Darkfire Avenger DM/SD/Body Scrapper

Arc ID#161629 Freaks, Geeks, and Men in Black
Arc ID#431270 Until the End of the World

There are about 100012384986775893472875 ParaCon arcs and they all have their own charm. Who had the idea first? Who cares?

---

I'd be honored that someone thought my work was that good and happy he freed up a arc slot for me. Especially if he did it better.

---

This is very common.
I've heard it called the "100th Monkey" Theory :: http://en.wikipedia.org/wiki/Hundredth-monkey_effect

To me, it is no more or less than kicking down a wall into a new zone of the collective-unconscious or psychtronically connecting the dots of current social and media intake to come to the same or relatively same conclusions when trying to create in general.

You know, like Alexander Gram Bell and Marconi inventing the telephone at the same time, etc.

This is more common than many would think or want to believe is real.

I worked on an independent comic book years ago and, went I went to find a publisher, there was an author at the same convention that was selling a very similar story.
In fact he seemed shocked when I talked to him about the story I was working on and then showed me his. I immediately knew why he was shocked. I wasn't surprised myself as I have had this kind of thing happen before numerous times.
Both of our stories were picked up by different publishers. (This shows that even the publishers were in the same mindset in thinking that the idea would sell). They were by no means the exact same story, but they had many very similar traits and underlying themes.

I don't think it should upset anyone if something like this happens, because it happens all the time. I always take it to mean that you are in the right direction if other people are thinking the same thing.

This, of course, is completely different than seeing someone's work and thinking "I can do that idea better" ... which is something else entirely.

---

It's happened to me, and I enjoyed it. I used it as a learning experience to improve my own arc as well as making it more unique.

It's not a completely unique concept, but my arc #137561 Ctrl + Alt + Reset! is about a time loop, playing basically the same mission over 4 times in a row with subtle changes each repetition based on different player knowledge. One of my early feedback comments pointed me out to @jjac's arc A Tangle in Time, which is about a time loop, playing basically the same mission over 5 times in a row with subtle changes each repetition (and one major variation in mission 4).

I took what I saw in his arc that worked and figured out why it worked, and incorporated elements from that learning experience into my arc, though I eventually added more changes that took my arc farther away from his except for the basic time loop concept. I also directed him to my arc, which he played and gave me even more advice on how to make it work better. Neither one of us felt "ripped off", just thought of it as an interesting coincidence.

---