Can you measure the Earth's circumference from your bedroom window?

The thought experiment presented is an interesting blend of physics, philosophy, and the implications of measurement on reality. While it's not possible to directly measure the Earth's circumference from a bedroom without any external data or measurements, one could potentially use astronomical observations, such as the angles of shadows or the positions of celestial bodies at different times, to estimate it. However, these methods still rely on prior knowledge or measurements made by others. The author's conclusion that classical physics is a result of measurements and not a fundamental truth touches on the debate between realism and the role of observation in quantum mechanics.