In order to see and hear with any degree of accuracy and precision we must learn to keep the head still, which means adopting certain physical tensions, especially in the neck. What this means – to cut a long story short – is that our minds end up strongly privileging solidity over fluidity, permanence over transience, stasis over motion, sameness over difference, habit over change, and we find ourselves living in a rigidly safe (and boring) world because the mind is like a spoilt child – what it wants it usually gets. But, of course, despite our best efforts – subtle or forceful – the world is not really like that so the mind is in a state of constant stress trying to force its world to behave the way it wants. Hence anxiety, hence stiff necks, hence sore backs.