I was driving my mother from my sister Sue’s house to my own home last June when she said, “Sue has been my daughter her whole life. Why don’t I know her mother?”

It was as if my mother, whose mind had been steadily losing ground to Alzheimer’s, had become a Zen master dispensing koans.

I’d busied myself that spring establishing a sort of monastic discipline of my own, preparing for my mother to move in with my family and me for the summer. In an attempt to shape a habitat that would suit her increasingly unruly mind, I’d come up with a simple creed to which I vowed to adhere, and I’d encouraged my husband, Larry, and our daughters, Maddie and Anna, to subscribe to it as well. That creed was this: Things fall apart. Move on. This philosophy was intended to guide us in the areas of language, cooking, sleeping, bathing, and other daily activities that would be affected by my mother’s presence among us. Exhausted by prior attempts to impose reason and structure onto the madcap landscape that had become her world, I decided to eschew the holy order of the conventional and stop badgering my mother about the facts. Things fall apart. Move on.