Erich Gamma: A pattern is always a problem-solution pair that can be applied in a particular context. Although the solutions might look similar in different patterns, the problems they are solving are different. In fact from ten thousand meters most patterns solve a problem by adding a level of indirection. What is interesting is how this indirection comes about and in particular why it needs to happen.
Therefore if you just look at the solution to the problem, it isn't that enlightening and everything starts to look the same. When we wrote design patterns we often had this feeling??hey all started to look like the Strategy pattern.

http://www.artima.com/lejava/articles/patterns_practice.html