There are two kinds of people in the world; rivers and reservoirs.
A river-type person is someone who hears a new view point or thinks of something new and then goes out and tells his friends about it. He lets the new found knowledge flow through him like a river. That type of person gushes their new thoughts onto other people around them. They put new ideas into motion.
However, your reservoir-type people are the ones who hear new and exciting ideas, and rather than sharing it with the world, they store it for later use. These people hoard the knowledge and save it as a reservoir.
I don't remember exactly where I heard about this concept, but it makes sense. There's a quote by George Bernard Shaw that comes to mind. He says:
"If you have an apple and I have an apple and we exchange these apples then you and I will still each have one apple. But if you have an idea and I have an idea and we exchange these ideas, then each of us will have two ideas."