You'll challenge your friend's philosophies, pushing them to think in a more progressive direction than they already do. What you may not get about them, though, is that they already possess a sharp mind and a broad view of life's possibilities. Often you'll push them to think bigger and weirder simply for the sake of weirdness itself, when they are actually seeking true knowledge, understanding and a philosophy that holds up to reality.
Your influence could distract them in their thinking, rather than helping them focus and become more truth-oriented. For their part, they'll goad you as well. But what's the point? The best relationships teach you something important about yourself, but this one may be more about egging each other on. On the more positive side, there will always be a sense of spontaneity and adventure between you.