Some time ago I found this amazing video on game mechanics design by Will Wright, creator of The Sims franchise, SimCity and Spore, talks about game design principles. I like this because it really gave a lot of perspective in my game design experience. I like the way he connects the concepts and the way he uses metaphors to explain them. In particular, the definition of the possibility space for the player helped me as I started involving myself with game design.
I think it’s worth sharing, and by the way, I really think this video is much much better that the TED talk he gave.