WAS THIS WHEN it began? I was talking to my father on the phone. I was in Australia and he was in England. I was giving him some personal news when he suddenly broke in and said “Bye!” just like that, and hung up. I stared at the receiver for a long while before replacing it, wondering if I’d heard right.

Was that the first sign, the first small uncharacteristic act that should have warned me that something was amiss? But is it really possible to pinpoint the first sign? The medical evidence is that, with this particular disease, the first distinct manifestations represent a later stage in the whole process. They’re like the first bubbles in water that’s approaching boiling point; they mark a point in the heating process begun some time before. There may have been many signs that my family and I missed or ignored simply because we weren’t looking. The phone incident was one. After my initial astonishment, I thought nothing more of it and told no one about it. I just made a note of it in my diary.