One becomes Two

Before Two becomes One (look at previous post), there are times, when you walk along a street, that you can catch with the corner of your eye a One that becomes Two. The important thing to remember is that you can see it only with the corner of your eye, because this action is the beginning of much trouble - and in life we can catch these decisive moments only when we are not looking straight at them. It's what Douglas Adams has brilliantly defined as a "S.E.P. field". I am quoting: "Somebody Else's Problem field, or SEPis a cheap, easy, and staggeringly useful way of safely protecting something from unwanted eyes. It can run almost indefinitely on a torch (flashlight)/9 volt battery, and is able to do so because it utilises a person's natural tendency to ignore things they don't easily accept, like, for example, aliens at a cricket match. Any object around which an S.E.P. is applied will cease to be noticed, because any problems one may have understanding it (and therefore accepting its existence) become Somebody Else's. An object becomes not so much invisible as unnoticed. An S.E.P. can be seen if caught by surprise, or out of the corner of one's eye".