In conclusion: we have problems perceiving non-events. We are blind to what does not exist. We realise if there is a war, but we do not appreciate the absence of war during peacetime. If we are healthy, we rarely think about being sick. Or, if we get off the plane in Cancun, we do not stop to notice that we did not crash. If we thought more frequently about absence, we might well be happier. But it is tough mental work. The greatest philosophical question is why does something and not
