“even the motion itself can not be uniquely defined because neither its temporal nor spatial factors can be uniquely defined. (Young Einstein's daydream of flying with a light beam). Neither the arrow itself can be uniquely defined due to the relativistic effect on the mass of the arrow. But still, each defined path in space-time (so called "worldline" 世界綫) is precise. It is just not unique.”
其实，俺理解，老芝不过是在提示观察的角度与结论之间的关系。
而不是寻求一个确定不移的真相。
