I suffer from a motor neuron disorder, in my case a variant of amyotrophic lateral sclerosis (ALS): Lou Gehrig’s disease. Motor neuron disorders are far from rare: Parkinson’s disease, multiple sclerosis, and a variety of lesser diseases all come under that heading. What is distinctive about ALS—the least common of this family of neuro-muscular illnesses—is firstly that there is no loss of sensation (a mixed blessing) and secondly that there is no pain. In contrast to almost every other serious or deadly disease, one is thus left free to contemplate at leisure and in minimal discomfort the catastrophic progress of one’s own deterioration.

In effect, ALS constitutes progressive imprisonment without parole. First you lose the use of a digit or two; then a limb; then and almost inevitably, all four. The muscles of the torso decline into near torpor, a practical problem from the digestive point of view but also life-threatening, in that breathing becomes at first difficult and eventually impossible without external assistance in the form of a tube-and-pump apparatus. In the more extreme variants of the disease, associated with dysfunction of the upper motor neurons (the rest of the body is driven by the so-called lower motor neurons), swallowing, speaking, and even controlling the jaw and head become impossible. I do not (yet) suffer from this aspect of the disease, or else I could not dictate this text.

By my present stage of decline, I am thus effectively quadriplegic. With extraordinary effort I can move my right hand a little and can adduct my left arm some six inches across my chest. My legs, although they will lock when upright long enough to allow a nurse to transfer me from one chair to another, cannot bear my weight and only one of them has any autonomous movement left in it. Thus when legs or arms are set in a given position, there they remain until someone moves them for me. The same is true of my torso, with the result that backache from inertia and pressure is a chronic irritation. Having no use of my arms, I cannot scratch an itch, adjust my spectacles, remove food particles from my teeth, or anything else that—as a moment’s reflection will confirm—we all do dozens of times a day. To say the least, I am utterly and completely dependent upon the kindness of strangers (and anyone else).

During the day I can at least request a scratch, an adjustment, a drink, or simply a gratuitous re-placement of my limbs—since enforced stillness for hours on end is not only physically uncomfortable but psychologically close to intolerable. It is not as though you lose the desire to stretch, to bend, to stand or lie or run or even exercise. But when the urge comes over you there…