PROSPECT The Journal of an Artist By Anne Truitt; Scribner: 221 pp., $22

Written by a woman “preparing to reach the end of a long life,” the prospect of the title is, as Anne Truitt makes clear, old age and death. Yet far from being gloomy, Truitt’s outlook, steadied by fierce intelligence, adaptability, detachment (learned reluctantly from her mother and keenly from Cicero) and, most strikingly, a passion to cut to the meaning of every experience makes her an optimistic, even exemplary guide through this territory that awaits us all.

Entering her 70s, she is in crisis: Her art no longer sells; she finds herself powerless to protect her family from life’s painful vicissitudes of illness, early death, divorce and suicide; she views her own approaching death with anxiety.

Crushed by [her art] exhibition’s total financial failure, she suddenly realizes “that my attachment to my work as a kind of justification for my life is the very self-deception that I have sometimes smugly criticized in others.”

Her journal becomes the catalyst through which she reconciles her past and future. By the time she has finished her book, at 72, Truitt has learned transforming lessons: that living with insecurity “is critical to psychological growth . . . that character changes little over time; that a life, like a sculpture, cannot be brought to a ‘tidy end,’ ” that aging is “the most interesting thing that has ever happened to me.” Closing this sage portrait of the artist as an old woman, I believed her.