Physicist: The problem with magnetism and the electric force is that they tend to cancel themselves out. For example, if you have a positive charge the first thing it does is repel all the other positive charges around it and attract all the negative charges. In your body right now you have somewhere in the neighborhood of 1028 or 1029 (between ten and a hundred thousand trillion trillion) charged particles in the form of protons and electrons. Gravity, on the other hand, has only one kind of “charge”: matter. All matter attracts all matter, so despite being far and away the weakest force, gravity is basically the last man standing on large scales.