"The Little Book of Common Sense Investing" by John C. Bogle emphasizes the importance of low-cost index funds for long-term investment success. Bogle, the founder of Vanguard Group, advocates for a simple, straightforward approach to investing that minimizes fees and maximizes returns over time. The book highlights the benefits of passive investing, arguing that most actively managed funds fail to outperform the market. By investing in a broad market index, individuals can achieve better financial outcomes while reducing risk and complexity in their investment strategies.