Well, if that which is not there is difficult to see, that which is obvious, plain and evident, is at times even harder to notice.
You will agree though that the obvious is hard reality.
Missing the obvious makes us look stupid. Not missing it preserves us from danger, from loss and from disappointment and grants our judgement to be sound and wise.
But do fishes notice water? No, it is all around them. Is water vital for fishes? Certainly, it is.
Indeed, there are many manifest and meaningful things around us on clear display, lying there on our way; some we see, but some important ones we pain to notice, and only if we turn our heads towards them with intent and rub our eyes.
The obvious things turned invisible, like chameleons, are those that were around us or with us so long that they became received tradition, part of the furniture, part of the unquestioned background, self-evident beyond suspicion, or even part of us.
Much worse, the obvious keeps invisible for us in a way even more perverse: there is a number of things we know about as evident, but for various reasons we cannot or avoid understanding them. The obvious known, comes alive for us to do something about it only when understanding turns it into image, vivid and simple enough to be of our size; otherwise we stay paralysed and dumb.
The more I stumble into the obvious unawares, the more it rules over me; as I discover it, I navigate my little boat to freedom.
(Want to read more about the secret life of the obvious?)