hi. as a non-physicist reading physicsbokks i have a problem understanding how, in richard feynmans words, "time itself", is measured. feynman seems to move from clock-measurement to "time"-measurement without a justification. as tsr clairly states time-dilation i have a problem of understanding the terminology. do we talk of "time going slower" or of "clocks going slower"? this might seem ridiculous, but it is a point i simply do not understand when reading feynmans "six not so easy pieces" and other semi-introductory descriptions of the theory of special relativity.