As Ms. Ehrenreich disapprovingly explains, positive thinking has saturated not just American religion but also corporate life and popular culture, and it is rapidly soaking into modern psychology. The problem for her is that people who are insistently reciting inspirational phrases won't hear the siren's wail in time to save themselves. Ms. Ehrenreich cranks her indignation up highest when aiming at the bankers, economists, bureaucrats and business honchos whose near-hallucinatory positive thinking, she believes, has pushed us all to the brink of economic collapse.

Like any polemic, Bright-Sided occasionally overreaches, especially when Ehrenreich blames the Iraq war and the current economic collapse on positive thinking run amok—such large-scale events never have a single cause. Overall, though, Ehrenreich offers a convincing critique and an alternative route to happiness that resonates in these difficult times.

After receiving a diagnosis of breast cancer, she was horrified to find herself beset by well-meaning therapists and fellow-patients and marketers, all of them urging her to accept “the gift of cancer” (which is the title of an upbeat book written by a survivor), to festoon herself with garish pink ribbons, and, above all, to stay positive. Her defiance of these directives seems both mischievous and righteous, although equally mischievous readers might recognize the outline of a rather conventional story. Most self-help books start this way, with frustration, and most of them end with the protagonist at peace, or closer to it, having reconciled herself to a more sophisticated form of the thing she started out by rejecting.