I have very fond memories about my high school maths and physics teacher. He is the one responsible for my love for science and the first who tried to teach me how to use my own brain and think freely.
He stressed the subject of inertial frame of reference, a kind of “independent observation point”, quite a lot. Think of when your sitting in a train and the train next to you moves: you have the impression that the train you’re on is moving. From the inertial frame of reference of the guy on the platform, it is clear which train is moving. My high school teacher loved to bring up Galileo’s struggle to convince his contemporaries that the Earth was revolving around the Sun, not the opposite, as most believed at those times.
My physics teacher argued that they were actually both right, both points of view had their own reasons based on physics if you observed them from the correct inertial frame of reference.