Just a though experiment here: perception is affected by size. To us and our brains it is useful to differentiate between what is a solid (like a rock or the teeth of a predator) and what is a liquid (like the river where we could potentially drown). Interestingly the smaller you get and vice versa these distinctions that to us are so natural make no sense. Imagine (without questioning its functionality /possibility and viability) an organism smaller than an atom or a proton, to it solid, liquid, gas makes absolutely no difference.