Matter is only +ve and -ve
ag) All particles, even neutral ones are detected as +ve or -ve. With neutral ones detected as net zero.
ah) So there are only two particles. +ve, -ve, they have no mass (from x), and no since size comes from motion, then they also have no size.
Added: Nearly there, but you still need to understand the nature of space, and why the speed of light appears to be constant.