If we are to understand dyslexia, and how to consider it critically, fairly, honestly and truthfully, we have first to understand the fundamental science underpinning literacy. (This is an absolute requirement which many writers do not satisfy.) This elementary foundation is what my early chapters are all about. They are about how the brain does it – how does it read, write or spell? I begin with the basic, essential cognitive psychology of literacy without which there can be no real understanding of it. I explore how this discipline, so fascinating in itself, also enriches our thinking and our practice. There is some jargon ahead (as there must be) but only, I promise you, what is absolutely necessary and I explain it all in plain language as we go along.

I appreciate that the very phrase ‘cognitive psychology’ is sufficient to cause many readers suddenly to decide to make a pizza, or a start on painting the bathroom, so I feel I must mount a deliberate defence of, and eulogy for, this marvellous subject. It goes like this:

Be not afraid of a little cognitive psychology! It is much simpler, more fascinating and more empowering, and much more elegant, than you may think. Your mind does a plethora of things, and it does them all the time - it is doing many things ‘you’ don’t know about right now. It is tracking your position in space and maintaining it; it is tracking your physiological status and maintaining that; it is tracking your immediate environment and what is taking place in it and will alert you immediately to any important change; as well as reading this sentence it may be simultaneously (but secretly) ruminating about all sorts of other stuff relating to other aspects of your life. Unless something urgent arises among all this you may never know anything of any of it. Your mind is a fantastic device doing fantastic things, but it does almost all its work in secret obscurity. This is why we understand it so little and why we underestimate its profound quality so.

Cognitive psychology is a rather young science. It is the study of how your mind does all those complicated things we presently regard, in our ignorance, as simple - things like instantly recognising people, breeds of dog, makes of car or words on the page; understanding speech or text; speaking or writing; remembering shopping lists, birthdays, smells, melodies, the names of footballers, film stars or philosophers; walking and chewing gum at the same time; making pizza or painting the bathroom.

Whatever you do, your brain will have driven the process. No brain, no process. (The phrase ‘no brainer’ shows how we undervalue this superlative organ! Until you are dead, everything is precisely a brainer. The thing is everywhere and responsible for everything.) It must be admitted, though, that your mind is mysterious and obscure. It is easily overlooked because its processes are almost always modestly unconscious. You neither notice these activities, nor, frankly, do you appreciate them. You just accept their discreet competence and magical reliability. You correspondingly seldom see all this as the tour de force it really is. I was about to say ‘mind boggling tour de force’ but of course your mind was not boggled at all. It almost never is. Your mind is modest, but miraculous. It is constantly deluged, at high speed, with uncountable volumes of detail, some of which will prove important but much of which is either trivial or actually irrelevant. This flood of information has to be absorbed, filtered, analysed, considered, prioritised, mixed and matched or discarded before even the simplest perception or decision can be plucked from it. Your brain is literally fabulous. You do these unimaginably complex things all the time, without effort and without even noticing, never mind understanding how. This is truly magical. Cognitive psychology is magical too, though. It unpicks one sort of magic, that of awed ignorance, but replaces it with another, and better, magic, that of awed understanding. The awe remains.

How is cognitive psychology different from what we usually mean by ‘psychology’? Cognitive psychology deals ‘only’ with the normal brain’s everyday activities as it manages the everyday. It does not speculate about our relationship with mother, ask us to interpret ink blots, free associate or invoke ego, superego or id. Cognitive psychology is less and more than this. It is the study of the ‘how does it do that?’ question; the mechanics of mind. In our present context it deals with questions like: How do we read? Do we read letters or whole words? Do we read visually, or do we read sound? How do we recall spellings? How do we learn them in the first place? Do we use rules? What else could we use?