I recently came across an example of a fictional 2 dimension being and how that being would experience 3 dimensional interaction. In this is example the 2d being was on a pool table and would only see flashes of the pool balls as they interact with the 2d plane. Is gravity similar; however, a function 4d interaction with 3d space? Could gravity exist without space-time? Since all matter experiences gravity, one way to define it would that the 4th dimension causes all 3d points to reflect back on itself when experiencing "time" thereby creating what we experience in the 3d as gravity. Additional, gravity, in my opinion, seems to be a function of motion. It seems to be common understanding that time is a function of the 4th dimension and motion is function of time. Therefore the two are mutually inclusive.