THE PRIVATE LIVES OF TREES (ALEJANDRO ZAMBRA) AND THE OBSERVATOR´S POSITION AS THE CENTER OF THE FRAME OF REFERENT

Focus your gaze on the current: the bridge moves forward, we move forward, the water is still, it comes to a halt. That is what Julian, her step father, said on the bridge where he used to take her when she was a child. At the begining it is difficult but then you get used to it, it is like those strange drawings which you have to stare at until you see a figure, a dragon, a bear, somebody´s face; one more time, look, focus your gaze, keep your eyes on the water until you feel you move forward, that the bridge moves forward, until the river is not a river any more. The water loses velocity, and now it is you who moves forward in the water, in a ship

Newton´s first law doesn´t distinguish between an object in rest and an object with uniform linear motion, it´s the same state, and the different perception only depends on where the observator is. Many situations can explain this phenomenon, my favourite is the traveller who looks out of the train window (the train is the most complete experience as a observator traveller) how a cow who is looking at him moves back. But the cow is motionless and sees how the train progresses. Indeed, both of them, traveller and cow, move together with Earth around the Sun