When a tree falls in the forest, does it make a sound? What a silly question: It's just semantics! Of course, it does release acoustic energy, when its motion

When a tree falls in the forest, does it make a sound? What a silly question: It's just semantics! Of course, it does release acoustic energy, when its motion causes vibrations in the air. If there is no one near enough for this energy to move their eardrum and be perceived by the brain, no one will hear the tree fall. Likewise, are these landmarks in the right location? George is saying that the 4 Corners monument and the Greenwich meridian were supposed to be at certain points, and they were installed at different points. You're retroactively redefining those points to be "where the monuments are". It's perfectly reasonable to talk about the difference between the intended position and the actual position, and when the intended position makes more sense - for example, going X degrees east or west of the meridian should put you at X degrees. If the meridian does not go through the axis of rotation of the earth, so that measurements at other points do not put you at X degrees, it's sensible to say that the meridian is off.