the mischief irretrievably done — "a volume that’s come to mean…"

The book that snaps Lenz to himself: a large-print William James found behind an Ennet bookshelf, and the line about "the mischief is irretrievably done" that catches him mid-relapse-anatomy. The recovery house as an accidental site of reckoning — the addict caught out by a nineteenth-century psychologist's sentence about the damage already, unknowingly, prepared.