The human brain is that object, and its wonder survives every attempt to make it sound dull. Upwards of eighty billion neurons, each wired to thousands of its neighbours, produce between them a number of possible connective patterns so vast that it dwarfs the count of atoms in the visible cosmos. That is not a figure of speech deployed for effect; it is arithmetic. You are, at this moment, operating a piece of equipment whose intricacy exceeds anything humanity has built or is likely to build. The instruction manual, admittedly, was never supplied.
Before we go further, consider the sheer unlikelihood of your arriving here at all. Every one of your ancestors, stretching back through an unbroken chain to the first flicker of life, managed the one non-negotiable feat of surviving long enough to reproduce. Not a single link failed. The meeting of one particular pair, repeated without interruption across an incomprehensible span of time and reshuffled at each step by a lottery of inheritance, has produced precisely one of you and will never produce another. The odds against your existence are so steep that, strictly speaking, you ought not to be reading this. And yet here you sit, defying the mathematics, with the temerity to feel ordinary.
The truly singular thing, though, is not merely that you exist, but that no one has ever thought as you think. Two brains may share a species, a language, even a family resemblance of temperament, and remain as different as two hands of writing. Your own web of associations — the way one word summons another, the private cross-reference between a childhood smell and a piece of music, the peculiar route your attention takes through a problem — has been laid down by a life that only you have lived. It is a fingerprint pressed not on glass but on thought. No machine can reproduce it, since it has no biography of its own. What you carry between your ears is, in the most literal sense available to us, unrepeatable.
Which raises the impertinent question of why so few of us appear to enjoy it. We are inclined, the intelligent animal, to treat our own minds as a household appliance — useful, taken for granted, noticed chiefly when it breaks down. We fret that we are not clever enough, forgetting that cleverness was never the measure. We envy the recall of a rival or the wit of a stranger, as though genius arrived in a single flavour and we had been served the wrong one. The unfashionable and liberating truth is that there is no such thing as an unintelligent person — only a magnificent one who has not yet been shown where the switches are.
To use the thing well is among the greatest satisfactions available to a human being, and one of the few that improves with indulgence. A mind stretched by a fresh idea, as the old line has it, never returns to its former dimensions. Better still, and contrary to the gloomy folklore of ageing, the brain that is worked does not wear through like a shoe; it grows richer in its connections the more it is asked to do. We are, alone among our possessions, the one thing that appreciates through use rather than depreciating with it.
None of this lasts, of course, which is the final argument for savouring it now. The precise constellation of memory and appetite and folly that answers to your name is on loan, not freehold; it flickered into being against staggering odds and will, in time, flicker out, and the cosmos will not trouble to assemble another. That is no cause for gloom. It is the best imaginable reason to relish the improbable, unrepeatable, faintly ridiculous privilege of being an intelligent human — which is to say, of being you, and no one else who has ever lived.
