If you’re looking for a practical, good-for-you guide to keeping your sanity in our complicated, overstimulated society, look back…way back…to the ancient Greco-Roman philosophy of Stoicism. You’ll be in good company. Stoicism is all the rage in Silicon Valley, on Wall Street—­Warren Buffett, Jeff Bezos and Bill Gates often are described as following ­Stoic principles—and in books, online courses and live events.

Why follow a way of approaching life that dates back to around 300 BCE? Human nature still is pretty much the same—people want love, wealth, children and respect, and they still are afraid of disease, natural disasters, poverty and being spoken ill of. As much as ever, people today need a framework to orient themselves, set priorities, appreciate the good and handle the bad.

Stoicism may sound simple, but once you start to apply its principles every day, it’s remarkably liberating.

Stoicism is not about suppressing emotion (à la Star Trek’s Mr. Spock) or being so self-reliant that you don’t need anyone. What it is about, fundamentally, is recognizing that each of us can control only our own judgments, decisions, intentions and behaviors—we can’t control outcomes. If you’re not successful, learn from it and move on. It’s that two-part approach—­living in the moment but always striving to become a better person—that gives this ­philosophy its edge. When making major decisions, Stoics consider the following four “cardinal virtues”…

Practical wisdom: The knowledge of what is good and bad, and what needs to be done.

The knowledge of what is good and bad, and what needs to be done. Courage: Not just physical courage but also the moral courage to face daily challenges with clarity and integrity.

Not just physical courage but also the moral courage to face daily challenges with clarity and integrity. Temperance: The exercise of self-restraint and moderation in all aspects of life.

The exercise of self-restraint and moderation in all aspects of life. Justice: Treating others fairly even when they have done wrong.

At the root of Stoicism is respect for other humans. The ancient Stoics were the only major group of free people at the time who were openly opposed to slavery and who thought that women were full-fledged human ­beings. Here’s how ­classic Stoicism might help you ­approach some very modern challenges…

Modern challenge: “I’m under constant stress.”

Stoic approach: Stress is not something that is placed upon you—it comes from your own misguided expectations, from being too attached to certain outcomes and from trying to control things that are not within your control.

Say, for example, that you wanted to finish preparing a room in your house for your aging parents to move into and you didn’t get it done by your deadline. Accept that, and don’t wallow in regret—remember that you can’t always control outcomes. But at the same time, learn from the experience.

There’s a key Stoic practice that can help—end each day by writing answers to three questions in a diary: What did I do wrong today? What did I do right today? What could I have done differently today?

Modern challenge: “I have relentless demands on my time.”

Stoic approach: Recognize that time is your most precious resource. Don’t easily give it away—it can never be paid back—and don’t fritter it away. Learn to say “no” when people ask for more time than you can comfortably give. Look at it this way: If a friend asked to borrow $10,000 but you had only $5,000 to spare, that’s all you could offer. In the same way, don’t “steal” time from people who really matter to you. ­Remember—Stoics place a strong emphasis on responsibility to family and friends.

Modern challenge: “I waste time on the Internet and feel bad about myself.”

Stoic approach: Technology is neither good nor bad. It is what it is. But how you use it—what’s under your control—can make you a better person.

I am active on Twitter for my job. I curate, share other people’s work, follow people who make interesting suggestions, etc. But I can’t engage with all my 25,000 followers—and when a follower is insulting or aggressive, I exercise my Stoic virtues of temperance, courage and justice by not responding…deleting a post…and/or unfollowing. In fact, digital technology is like being in a “virtue gym”—it gives you constant opportunities to exercise your ethics and character.

Modern challenge: “Even though I’ve done OK financially, I’m never content with my wealth and possessions.”

Stoic approach: There is nothing in Stoicism that says wealth is bad or that you shouldn’t use it to live a good life—ancient Stoics ran the financial gamut from slaves to emperors. But money is very consciously recognized in Stoicism as a great temptation—the more people have, the more they become focused on possessions and expensive experiences…always wanting more.

How to free yourself? Recognize that possessions are external objects that you can lose—you’re lucky to have them, but that luck can turn at any moment. That may sound scary, but it’s actually quite liberating. You’ve already mentally accepted the worst possible outcome…which actually is unlikely to take place. Some Stoics periodically “practice” not having things they do have. Why? To get used to the idea that everything they think they own actually is borrowed from the universe, so to speak. Examples: They regularly fast for a day or more to better appreciate the next meal…take cold showers to remember what a privilege it is to be able to take a hot one. Did your favorite mug break? Even 10 seconds of upset is unnecessary. Tell yourself, It was a mug. I knew it could break.

Modern challenge: “I’m getting older, and I constantly feel worried about my health.”

Stoic approach: Recognize what you can control and what you can’t—and let go of the desire to control outcomes. You can eat right, exercise, avoid cigarettes, etc., and make medical decisions based on empirical evidence, but you can’t truly control whether you get sick or what the outcome of any illness is. In a sense, worrying too much about ourselves is a form of narcissism, an ­attitude that Stoics avoided by reminding themselves of their place in the infinity of space and time, a meditation practice known as “the view from above.”

Modern challenge: “I’m afraid of ­dying.”

Stoic approach: Death is natural and inevitable, and we need to accept it or we will not be truly happy during life. Part of accepting death is preparing for it, yet many Americans have no will, no power of attorney, no ­do-not-resuscitate order. Stoics consider it courageous to prepare for the end of life, and it can be a refreshing exercise. And according to Seneca, one of the great Stoic philosophers, the ultimate test of character is how one handles the last moments of life.