Reasonable > Rational

You’re not a spreadsheet. You’re a person. A flawed, emotional, complicated person. Aiming to be mostly reasonable works better than trying to be coldly rational. A reasonable strategy you can stick with beats an optimal strategy you’ll abandon.

The best financial plan is not the one that maximizes returns—it’s the one you can actually follow through tough times.

Rational vs. Reasonable

Rational: The mathematically optimal strategy, regardless of how it makes you feel

Reasonable: A strategy that makes sense to you and that you can stick with through thick and thin

Academic finance is devoted to finding the rational strategy. Real-world success comes from finding a reasonable one.

The Fever Example

Fevers are actually your body’s rational response to infection—the heat kills bacteria. But a fever is miserable. So we take medicine to reduce it, even though that’s technically working against our body’s optimal strategy.

This is rational. But it’s also reasonable to reduce your suffering. In finance, the same logic applies: sometimes the “suboptimal” strategy is the right choice because it’s the one you can live with.

Examples of Reasonable vs. Rational

The Home Ownership Example

From a purely rational standpoint, owning a home often doesn’t make financial sense. Renting and investing the difference can yield higher returns. But home ownership provides something hard to quantify: stability, pride, community connection.

Telling someone not to buy a house because the math doesn’t work ignores that humans aren’t spreadsheets. The psychological benefits of ownership might be worth the financial cost.

What You Can Stick With

The best investment strategy is not the one with the highest expected return. It’s the one you can maintain through:

• Market crashes that feel terrifying
• Periods of underperformance that test your faith
• Life events that stress your finances
• Friends bragging about their returns
• Decades of time when anything can happen

Love Your Investments

Housel argues there’s something to be said for loving your investments. If you’re passionate about a company and genuinely enjoy following it, you’re more likely to stick with it through downturns. Pure optimization misses this.

The same applies to your career: a job you love that pays less might make you happier and more successful in the long run than a job you hate that pays more.

The Danger of Optimization

The pursuit of the optimal strategy can paralyze you with analysis. Or worse, it can lead you to a strategy that’s theoretically perfect but practically impossible to maintain. Don’t let the perfect be the enemy of the good.

Making Peace with Good Enough

A reasonable financial life involves:

• Accepting that your strategy won’t be mathematically optimal
• Prioritizing what helps you sleep at night
• Making decisions your future self won’t regret
• Finding the balance between return and peace of mind

Key Takeaways

• Reasonable beats rational: A strategy you can stick with beats one you’ll abandon
• You’re not a spreadsheet: Emotions, relationships, and peace of mind matter
• Psychology counts: The “right” strategy is the one that works for your psychology
• Good enough is good enough: Don’t let perfect be the enemy of good
• Sleep matters: If your strategy keeps you up at night, it’s not the right strategy