I was thinking when I take the Lorentz formula for a location γ.(x – v.t) as an observer in S and find the ratio compared with the location for an observer within the inertial system S’ it selves: 1/γ . Δx But I made a mistake and took 1/γ. x When I use the found ratio (for derivation, see attachment) for the time as an observer within the inertial system it selves: 1/γ. t, I find the Lorentz formula for time as an observer in S, but only for light x=c.t Why is this accidently right ?