Is it possible to steal ideas?

After a two hour discussion on the subject of ideas and innovation, my mother in law introduced a question she believed I could answer. The question was as follows: "Is it true that the Facebook guy stole somebody's idea, as the movie portrays?" It was a very good question. I knew I could only answer by defining the idea of an idea.  I've seen the movie (good one by the way), but I really don't know the whole story behind the start of the idea , and I have never been interested in the conception of Facebook.  In fact, "The Social Network"  does not influence my thinking, but it has reinforced my feelings towards idea execution and business. I do not believe it is possible to steal ideas. 

My answer was as follows: "No, he didn't stole somebody's idea. Nobody "owns" an idea. You can't patent an idea. You patent the process. A working concept is a process being built, not an idea." I have come to understand that we tend to ask questions which consciously and unconsciously align in one way or another to our thoughts and needs for information. We complete our own theories with questions and we answer these with communication, reading and vision. This natural process helps us form opinions which in turn helps form ideas, concepts (sets of ideas which interact), and vision. The world is not inundated with "idea thieves", it is not possible to steal ideas.   There are many examples we could use around this topic. My belief is that this one in particular (Facebook), became popular because of its tremendous success as a social networking platform. An idea is a thought about how something should work. It is an answer to a question that has been generated by the mind. An idea is  not a fully proven step-by-step guide you can follow through with ease of completion. People have to build their ideas into concepts and then follow through by making and executing a plan.

People do not steal ideas.

However, people have been known to steal a plan. 

 "The unanswered question is the one unasked." - Unknown