common-sense-index-investing-bogle

Overview

This skill distills John Bogle's The Little Book of Common Sense Investing into an agent-ready decision framework. It covers fund selection, cost evaluation, asset allocation, and the case for index investing. Intended for individual investors, financial advisors, and anyone evaluating their portfolio strategy.

When to Use This Skill

• User asks whether to use index funds vs. actively managed funds
• User is comparing mutual fund options and wants a cost-based analysis
• User asks about asset allocation between stocks and bonds
• User is tempted by a "hot" fund or recent top-performer
• User asks "is this fund manager worth it?" or "should I follow past performance?"
• User asks about long-term wealth building strategy
• User asks about ETFs vs. traditional index funds
• User asks about retirement investing or target-date funds

Core Principle

The relentless rules of humble arithmetic: Investors as a group must earn exactly the market return before costs. After costs, they must earn less. Therefore, the only guaranteed way to capture your fair share of market returns is to own the entire market at the lowest possible cost — a traditional index fund held forever. Attempting to beat the market is a loser's game; it enriches Wall Street at the expense of Main Street investors.