Both summaries present happiness as the driver of success. One explicitly states “Happiness fuels success, not the other way around,” while the other explains that happier people are more likely to succeed at work and also enjoy deeper relationships and better health.

Both titles are listed in paperback format and show a page count of 256 pages.

Both summaries link happiness to better health and stronger social connections. They note improved health outcomes (including a stronger immune system and longer life), lower stress, and deeper, more satisfying social interaction.

Both books draw on research. One cites original research including large studies, and the other describes its approaches as research-based—presenting tested “happiness triggers” and evidence to support its recommendations.

Product details list a suggested age of 22 years and up for these books.

Across the two listings, heights range from 6.98 to 7.9 inches, widths from 5.1 to 5.17 inches, depths from 0.6 to 0.73 inches, and weights from 0.45 to 0.49 pounds.