When Newton perceived the apple fall to the ground and proposed the principles of Gravity, why did he assume that the apple fell to the ground and not that the earth and everything else was pulled towards the apple ? It is perfectly plausible the other way round too as the earth is not a solid structure but a mass of particles that ‘seemingly’ bind together to give the illusion of a solid mass. Similarly we keep thinking about light and other particles being pulled into ‘Black Holes” – why do we not see that as the smallest particles also pulling the black holes towards them ? Why do we imagine such ‘movements’ towards ‘objects’ that we imagine to have a greater mass and therefore greater gravity ? Partly because the concept of ‘distance’ is perhaps an imagined and perceived illusion. Effectively in modern particle physics and in what my uneducated mind understands from the string theory, there is no distance between anything as all is effectively part of an all encompassing ecosystem. Even the theory of Dark Matter seems to be saying the same thing. So how can the idea of gravity be proved at all if there is no ‘distance’. Any physicists out there ?