Your body is your property because only you are allowed to determine what happens to it. Now saying it's not property because it's special is like saying your

Your body is your property because only you are allowed to determine what happens to it. Now saying it's not property because it's special is like saying your car is not your property because it's special (e.g. with respect to traffic law). It can be both: special and your property. The whole thing is a relic of a weird system of law.