Hi, i asked some quesitons about this before but i need a clarification. Generally we use vertical light clocks and compare the distances taken by light and since c is constant the longer path taken by the light means a dilation in time, from here we say every other type of clcok dilates in same ratio because if they differ in dilation we have a way of understanding who is "moving". We use this dilation and apply to the horizontal "moving" clock and we have the length contraction formula, but here i need some clarification, when we try to prove time dilation from horizontal clock we first have to accept that the length contracts along the direction of motion, so this time time dilation occurs as a result of length contraction. But we accept lenthg contraction from the vertical clocks' time dilation which brings us back to time dilation. so we use the result of time dilation if we try to prove time dilation by horizontal clock. Isn't this a paradox?Obviosly not but i couldn't get it. I hope i could define my problem well, thanks.