時光機 3

Cumulative concept of time, 10

You can travel to the future since your future-self contains your present-self:

you travel to the future as long as you, somehow, do not change your present-self.

However, you cannot travel to the past, because by definition, your past-self does not contain your present-self:

your present-self is neither part of the past, nor part of your past-self.

— Me@2011.08.20

2011.08.21 Sunday (c) All rights reserved by ACHK