Miller’s core argument is that spiritual awareness is innate and that it is an important component in human development. An implication of her work is that if you care about social mobility, graduation rates, resilience, achievement and family formation, you can’t ignore the spiritual resources of the people you are trying to help.

Miller defines spirituality as “an inner sense of relationship to a higher power that is loving and guiding.” Different people can conceive of this higher power as God, nature, spirit, the universe or just a general oneness of being. She distinguishes spirituality, which has a provable genetic component, from religious affiliation, which is entirely influenced by environment.

I’d say Miller doesn’t pay sufficient attention to the many secular, this-world ways people find to organize their lives. Still, it does seem true that most children are born with a natural sense of the spiritual. If they find a dead squirrel on the playground, they understand there is something sacred there, and they will most likely give it a respectful burial. They have a natural sense of the oneness of creation, and a sense of a transcendent, nonmaterial realm. Miller cites twin studies that suggest that the strength of a child’s spiritual awareness is about 29 percent because of broad genetic heritability, 24 percent because of family environment and 47 percent because of a person’s unique individual environment.

Spiritual awareness, she continues, surges in adolescence, at about the same time as depression and other threats to well-being. Some level of teenage depression, she says, should be seen as a normal part of the growth process, as young people ask fundamental questions of themselves. The spiritual surge in adolescence is nature’s way of responding to this normal crisis.

“Taken together,” Miller writes, “research supports the idea of a common physiology underlying depression and spirituality.” In other words, teenagers commonly suffer a loss of meaning, confidence and identity. Some of them try to fill the void with drugs, alcohol, gang activity and even pregnancy. But others are surrounded by people who have cultivated their spiritual instincts. According to Miller’s research, adolescents with a strong sense of connection to a transcendent realm are 70 percent to 80 percent less likely to engage in heavy substance abuse. Among teenage girls, having a strong spiritual sense was extremely protective against serious depression. Adults who consider themselves highly spiritual at age 26 are, according to her research, 75 percent protected against recurrence of depression.