Amongst amateur game designers, there is a widely-spread deep-seated paranoia that someone somewhere is trolling the internet looking for the next big game concept and is perfectly happy to steal their idea. I will admit that I've often struggled with this fear myself. After all, when you put a lot of time and effort into something, even if it's something completely intangible like an idea, there's a strong desire to protect it. So while it may be naive and a little self-absorbed to think that your ideas are worth stealing, it is still a pretty natural and valid response.
However, there are two very strong cases for sharing your work in an open manner. First, game design, more than any other form of entertainment, is audience-driven. The people who play it have an important, active role to play in the scheme of things. While a film or book can be interpreted differently by everyone, the work is still the same for everyone who experiences it. You will see the same scenes or read the same words as I do; whether or not we see them in the same light or read them in the same context doesn't change the media.
A video game, on the other hand, will always produce a different experience based on whoever is playing. So unlike other forms of entertainment, the experience taken from a video game is defined by those who play it, not just by those who create it. A game designer makes the game to a point, but once he's finished, the gamer takes over and 'finishes the job', so to speak. In that respect, all game design really is 'made for other people'.
Thus, in my opinion, trying to work on a game design from an isolated, sound-proof broom closet will inevitably lead to the kind of game that only the designer would ever want to play. In the coming posts, I will inevitably be sharing my ideas. What I consider a good idea may in fact turn out to be a horrible idea. I like to think that I would know the difference, but I've often been surprised when I work on something, show it to a few friends, and get completely negative feedback.
To think that an amateur or student game designer can tell the difference between a good idea and a bad idea is foolhardy; natural talent only goes so far. Thus, by sharing my ideas with the world, the world can then look me square in the eyes and tell me I'm an idiot. Or, more eloquently, If you don't know when you're making mistakes, how can you ever hope to learn from them?
The second reason not to hide your ideas away is that game development is inescapably a team-driven effort. Most games today aren't produced by a single person, but instead a large group of creative individuals each with their own idea of what's entertaining.
Of course, you could make the game all by yourself and hope nobody comes up with the same idea in the 20 years it takes you to make it. Assuming you live that long, since you'll be living in poverty; producing anything amazing is going to come with huge personal costs. For example, Braid cost Jonathan Blow $180,000 of his own money and took three years to produce. I don't think most of us have that kind of cash lying around or that much free time. Braid also wasn't made entirely by one person; David Hellman produced the art and all of the music is licensed.
The only realistic option for most of us is to study hard, dream big, and work with like-minded individuals (either at a job or through social networking) to get something done. You absolutely cannot go it alone anymore.
I consider the widening of the target audience and the greater odds that your game will actually be produced to be worth the slim chance that someone who reads your idea will have the opportunity to act on it and steal it away. As I've said, game design is largely concerned with making something for other people, and getting a better idea of what those people want to experience can, in turn, help to make better games. Or at least games that can reach a wider audience. If you're not concerned with that, that's perfectly fine; just don't get upset when all of that fortune and glory you feel your game design should be earning never materializes.
As I write in this space, I will try to be as completely open and forthcoming as possible, though I am sure that I will have a great difficulty exposing my fledgling ideas. In that regard, this post was written to address my own fears and concerns as much as those of other amateur game designers. I am sure I will look back on it whenever I get that sneaking suspicion that somebody is about to snatch up my life's work, and remind myself that the benefits far outweigh the risks. Life is far too short to hide your passion in a bubble.