Perennial Wisdom
Perennial Wisdom is a podcast for seekers and curious minds. Each episode explores philosophical and spiritual traditions for universal truths and enduring ideas to help you (and me) never stop learning how to live.
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Immanuel Kant: The Three Fundamental Questions
In this episode of Perennial Wisdom, we explore the life and thought of Immanuel Kant through the lens of three enduring philosophical questions: “What can I know?” “What should I do?” “What may I hope?” Drawing on Kant’s groundbreaking ideas from The Critique of Pure Reason and The Critique of Practical Reason, we walk through his views on knowledge, morality, and hope.
Kant’s philosophy offers us tools for navigating uncertainty, making ethical decisions, and sustaining hope in a complex world.
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Episode Transcript
The following is a transcript from “Immanuel Kant on the Three Fundamental Questions” from the Perennial Wisdom podcast (Ep. 249).
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Today’s episode focuses on a man whose quiet daily life changed how we think about knowledge, morality, and meaning—Immanuel Kant.
He was born in 1724 in Königsberg, a small city in East Prussia. He never traveled far from home. But the world he explored was far larger—the world of reason, ethics, and the human soul.
Kant once said that philosophy can be reduced to three simple questions:
What can I know? What should I do? What may I hope?
In today’s episode, we’ll walk with Kant through each of these questions, explore what they meant to him—and more importantly, what they might mean to us.
1. What Can I Know?
To understand Kant’s answer, we have to rewind a little. In the 1700s, philosophers were debating what we can truly know. Some, like Descartes, believed we could attain certainty by starting from the mind. Others, like David Hume, were deeply skeptical. Hume argued that what we think of as cause and effect—like fire causing heat—wasn’t something we could prove, just something we’re used to seeing.
Kant read Hume and was shaken. He said:
I freely admit: it was the objection of David Hume which first, many years ago, interrupted my dogmatic slumber.
So he set out to answer the question: How is knowledge possible at all?
And here’s what he proposed: The world doesn’t just shape our minds—our minds shape the world we see.
We don’t just see reality; we structure it.
Imagine wearing glasses with a built-in filter—one that organizes everything you see. That’s what Kant thought the mind does. We are born with built-in “categories” like time, space, and causality. These aren’t things we discover in the world—they’re tools we use to understand it.
So what can we really know?
Kant says we can know the world as it appears to us—what he calls phenomena—but we can’t access the world as it is in itself, which he calls noumena.
He summed it up with this famous line:
I had to deny knowledge in order to make room for faith.
We’ll revisit that “faith” part later. For now, his main point is this: science can tell us a lot about the world we experience—but it can’t answer the deepest questions about existence, God, or the soul. Those belong to a different part of us—our moral and spiritual imagination.
2. What Should I Do?
This is the heart of ethics. For Kant, morality isn’t about consequences or feelings. It’s about principles. A good person does what is right—not because it feels good or leads to success—but because it’s their duty.
He called this approach the categorical imperative. It sounds intimidating, but the idea is simple: Before you act, ask yourself: What if everyone in the world did what I’m about to do? Could I will it as a universal law?
If the answer is yes, then the act is moral. If not—it’s not.
Let’s take an example. Imagine you’re contemplating lying to get out of trouble. Could lying become a universal law? If everyone lied, then trust would collapse—and even the act of lying would lose its meaning. So it fails the test.
Kant writes:
Act only according to that maxim by which you can at the same time will that it should become a universal law.
He also adds another version:
Treat humanity, whether in yourself or in another, always as an end, never merely as a means.
In other words: never use people as tools. Respect their dignity.
Kant’s ethics is rooted in autonomy—the ability to govern yourself, to act from reason rather than pressure, pleasure, or fear.
And that takes courage.
This is similar to Socrates, who expressed during his trial that he would prefer to die than abandon the quest for truth. Socrates said:
The difficulty, my friends, is not in avoiding death, but in avoiding unrighteousness.
Kant agreed. To live well is to live morally—not just comfortably.
3. What May I Hope?
Here’s where Kant gets deeply human. He knew that life isn’t fair. The good suffer. The wicked prosper. The world is often unjust.
But morality, he believed, makes sense only if we can hope for a world in which justice prevails—even if it’s not in this life.
So he proposed something bold. He said: in order for ethics to be coherent, we must postulate three things:
(1) That we are free to choose.
(2) That our souls are immortal, so we can keep striving toward goodness.
(3) That God exists, to ensure the highest good is possible.
Kant did not intend to suggest that we can prove these ideas. He meant they’re necessary beliefs—because without them, the moral life falls apart.
Hope, for Kant, is a bridge between what we do and what we yearn for.
Final Thoughts
Kant said all three questions—”What can I know?” “What should I do?” and “What may I hope?”—lead to a fourth: “What is the human being?”
And that, ultimately, is the heart of philosophy. We are creatures with limits. We can’t know everything. We can’t control the world. But we can choose to act morally. We can think. We can hope.
That’s what makes us human.
So why does this 18th-century thinker still matter today?
Because Kant offers us a way to think about life in an age of confusion:
When we’re overwhelmed by information, he reminds us to ask, “What can I truly know?”
When we face ethical dilemmas, he challenges us to ask, “What should I do—not for gain, but for good?”
And when we feel lost, he gently asks, “What may I hope?”
These aren’t questions with quick answers.
As Kant famously said:
Dare to know. Have the courage to use your own understanding.
That’s the invitation he leaves us with. And maybe, that’s the start of philosophy—and a more thoughtful, meaningful life.
Reflection Exercise
Consider journaling or reflecting deeply on Kant’s three questions. Find a quiet space. Sit with these prompts slowly. Try to avoid rushing toward answers.
What can I know?
In what areas of life do I confuse opinion with understanding?
What assumptions do I rarely question?
What should I do?
Is there a situation in your life now that calls for moral clarity or courage?
What would it mean for you to act from duty, instead of desire?
What may I hope?
What is your deepest hope—for yourself, for the world?
How can your hope shape the way you live today?
Questions matter more than answers. We need to continually grapple (or wrestle) with these perennial questions as part of our ongoing journey to never stop learning how to live!
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Thank you for reading/listening; I hope you found something useful.
Until next time, be wise and be well.
J.W.
P.S. If you enjoyed it, consider leaving a rating on Apple Podcasts or Spotify.
I found the content corresponding closely with what the Bhagavat Gita conveys on all counts- except probably in regard to 'hope'. The Gita asks us to perform present tasks ethically (Satvik) with no expectation of the returns..