The Single Most Important Thing

If you had to name the single most important thing that could change your life, what would you say?

In our fast-paced, complex, and interconnected world, even asking ourselves this question feels like a luxury. But in doing so, we uncover something vital: time—the time to reflect. Time to pause, to think, to examine our lives. Reflection activates our System 2—the slow, deliberate, conscious part of our mind—and allows us to step outside of automation.

The Things That Shape Us

What truly matters to us tends to show up in what we do repeatedly. Our motivations shape our daily actions, and our actions define our lives.

Psychology has long tried to understand these motivations. One of the earliest and most influential models is Maslow’s Hierarchy of Needs (1943), which proposes a pyramid of human motivation: from physiological needs at the bottom to self-actualization at the top.

Introspection, the act of asking ourselves questions like “What really matters to me?”, clearly belongs to the top of that pyramid. It’s a luxury, yes—but a necessary one, if we want to take control of our life in this complex world.

But Are These Theories True?

Many modern theories of human motivation sound reasonable. But here’s a critical distinction: without empirical validation, theories are just conjectures. They may feel true — but (in general) feelings aren’t objective evidence.

Understanding what motivates us is difficult because motivation is complex. It emerges from the interaction between our mind (body) and environment. It cannot be easily isolated and objectively measured.

Researchers often try to study it through surveys, collecting data from real people. One such study tested Maslow’s common assumptions, such as:

1. Needs are satisfied in a fixed sequence
2. Income plays a major role in satisfying needs
3. The order of needs correlates with life satisfaction
4. Maslow’s sequence is the ideal path for all people

Surprisingly (or not), data violated all four assumptions. This is the power of empirical research: it challenges even our most widely accepted beliefs.

Facts Always Come with Context and Uncertainty

Scientific findings are never “absolute truths.” They are contextual and probabilistic. The above-mentioned survey, for example, was done in Mexico—it may reflect cultural influences. The way questions are asked, the order they’re presented in, and how responses are recorded can all affect results.

Good science works by acknowledging these limitations, reducing bias where possible, and estimating uncertainty. This is not a weakness—it’s the strength of the scientific method.

The Biggest Misconception

The scientific method is truly for everyone. It's the most reliable way we know to align our beliefs with reality. It asks us to:

• Look for objective facts, not just personal opinions;
• Acknowledge uncertainty and context;
• Be willing to change our minds in light of reliable and objective evidence.

If you think this is too abstract or detached from daily life, consider this: your car works because of science. Your phone, your shoes, your house, your medicine—all created by experts applying scientific principles. You trust their work every day.

It Takes Effort—but It Pays Off

Of course, applying this method takes effort. It’s not practical—or even possible—to use it for every single decision. But you can and should use it for the things you do repeatedly, because those are the habits and choices that shape your life the most.

In those cases, the effort pays off enormously, simply because science works. And the more you practice this mindset, the easier—and more rewarding—it becomes.

By examining whether the facts apply to your specific situation—and acknowledging the uncertainties—you’ll be better equipped to make sound, informed decisions.

Trust in Experts—But Stay Critical

To evaluate complex topics, don’t start from scratch. Leverage the work of experts—people who’ve dedicated years to studying and building knowledge in specific fields. Start with collective sources, such as professional organizations, academic reviews, or systematic studies, as biases are more likely for single experts.

Yes, experts can be wrong. That includes doctors, engineers, researchers—everyone. And indeed, also "AI-based experts" like ChatGPT. But that’s precisely why science builds on evidence, peer review, and replication. The solution isn't to reject expertise. It’s to apply the scientific mindset: stay curious, question everything, but first do your homework: inform yourself adequately on the objective evidence through the work done by experts. Healthy skepticism is essential—but uninformed dismissal is dangerous. Expertise requires time, training, and constant collaboration with other people: it has an enormous value that should be recognized.

This Will Change Your Life

Many people live disconnected from reality, making decisions based on assumptions, biases, and misinformation. This might feel comforting in the short term—but reality always catches up. Ignoring it doesn’t make it go away—it just makes the consequences worse.

If there is one thing you can do that will truly change your life, it’s this:

Not just in theory. In your actual choices. Your beliefs. Your habits. Your relationships. Learn to think in terms of evidence, uncertainty, and context. You don’t need to become a scientist—you already rely on science in every part of your life. Now, bring that power into your own mind.

It will change how you see yourself.

It will change how you relate to others.

And yes—it will change your life.

By applying the scientific method, you won’t just improve your own life—you’ll contribute to a better world. Because we need and depend on each other. We’re part of an intricate system of collaboration and mutual trust, and every one of us has a role to play. Every decision matters. Your actions matter. Your thinking matters.

And truth matters—even when it’s hard.