It is not logical if you really believe that speeds add linearly (that is, if you are going 5mph past an observer and throw a ball 5mph, that the result is the ball moving 10mph).
Speeds don’t actually add linearly like that, but they come very very very very close to doing so for all speeds humans are used to dealing with.
So, we all have very deeply held gut feelings that speeds should add linearly. Once you let go of that, it becomes much easier to understand many of the things that don’t feel logical about relativity.
Ultimately, it is logical, but from a different set of axioms than most humans tend to have.
But we don't really think that speeds add linearly. if you drive 80 kph North, and I drive 60 kph East, no one would say we are separating at 140 kph. we would use Pythagoras to get the right number.
We just don't realize we live in a 4D space where time is one dimension, so we think driving in opposite directions is a special case where we can add the speeds. but there is the fourth dimension, and we have to use an equation very similar to Pythagoras to get the right value.
I know you must know this, this is more for the benefit of the reader.
It is not logical if you really believe that speeds add linearly (that is, if you are going 5mph past an observer and throw a ball 5mph, that the result is the ball moving 10mph).
Speeds don’t actually add linearly like that, but they come very very very very close to doing so for all speeds humans are used to dealing with.
So, we all have very deeply held gut feelings that speeds should add linearly. Once you let go of that, it becomes much easier to understand many of the things that don’t feel logical about relativity.
Ultimately, it is logical, but from a different set of axioms than most humans tend to have.