Premise 1: Physics don't believe in sense "organs" of the human "robot" (more commonly said "common sense deceives us"). Premise 2: Physics believes in logic or mathematics. Background thrust: Quantum mechanics. Premise 3: Everything which "revolves" around the nucleus might not have identical properties. There might be some property of particles (revolving around the nucleus) which are not the same, because of our sense not detecting it. Then, we might say the particles to be identical only w.r.t our senses, but that is not the spirit of our physics, it must be proved logically. Or else we might define particles of such and such properties to be such and such, but that doesn't define them to be entirely identical. So, are particles revolving around the nucleus identical in all properties in reality? Or is there any logical or mathematical proof to show that the particles are all identical? The same argument can be applied to all the particles which we call identical.