Exercise Judgment


David Booth
Author of Stay Calm

Exercise Judgment

I went to work out one morning and saw that the market was down 2%. When I came back, the market was up 2%. So, what’s the investment lesson? Don’t forget to exercise!

You want an investing plan that allows you to stay calm during mornings like that. You can’t control financial markets, but you can control how you react to them. Then you can focus on things that matter to you, like exercise for me.

The market roller coaster is one of many unknowables in our lives. Big decisions don’t line up to be solved one at a time. The challenges of work, family, health, and money all crash into each other, often at surprising times and every now and then all at once. Our brains struggle to solve an equation with so many variables.

Understanding how markets work can help with one variable in the equation. You can build a financial plan that takes into account the range of outcomes your long-term investments may produce. You’ll keep monitoring the situation, but you don’t need to keep reacting to it.

You will need to be flexible, because many kinds of uncertainty don’t guarantee one outcome. A friend of mine told me about a golf shot he hit. He called it a “son-in-law” shot. “What’s that?” I asked. “Well, it wasn’t exactly what I hoped for, but it was pretty good.” That’s retirement for a lot of people. It may not end up exactly as you imagined, but it can still be pretty good. And for some people I know whose investments outperformed their expectations, they had a better retirement than they had hoped for.

Either way, keep exercising and doing the things that really matter to you and make you feel better. The market will be there working for you when you get back.

Stay calm, stay invested, and let markets work for you.

David

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Publishing September 2026

Warm, wise, and refreshingly free of jargon, Stay Calm is both a practical guide to long-term investing and a philosophy for living with clarity and confidence. Whether you’re just starting out, rethinking your financial plan, or guiding others, this book will change the way you think about markets, risk, and what really matters.

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Risks include loss of principal and fluctuating value.

Returns in USD.

US: Dimensional Fund Advisors LP is an investment advisor registered with the Securities and Exchange Commission.

CANADA: This material is issued by Dimensional Fund Advisors Canada ULC (Dimensional Canada) for educational purposes only and should not be construed as investment advice or an offer of any security for sale.

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