Space and time

I have had a problem with the space-time concept for quite some time. My main problem is this: to measure time, you need to observe a movement in space. Now, how can time be a dimension, if it’s definition is dependent on the existence of another dimension? It can’t, because that goes against the definition of a dimension. I once read that time is a dimension because if you were to meet someone, you need four coordinates, a location (x, y, z) and a time (t). While that seems reasonable, I was not convinced. For example, you also need to know who you’re supposed to meet, but the author did not suggest that the person was a dimension. Another problem is that, if we’re moving our 3D-flake of space through time like an iceberg on an ocean, how can time be relative? It’s like an airplane where only first class arrives at the destination. Wouldn’t it make more sense to assume that the perception of relative time is because the measurement of time is dependent on movement in space?

Yesterday, I stumbled upon a several articles by a Louis Savain, for example this, which seemed to confirm my disbelief. While he comes across as a quite angry man, he might still have a point. I cannot say I completely understood the argument he was giving, but I sense that he might know something about the problem with space-time that I would like to understand.