Quote Originally Posted by Byzantine Prince
Rate of change is represented by the derivative just fine. Thank you Leibniz!
Hey, unfair... I stated on the previous page. Ok not really the same but the intention is the same.

Call it what you will but the present is everchanging and it is never the same. What is has been has passed us by in a flash (well less actually). The rate of the passing by is time. That of course is not physical but so isn't thoughts.