Have you ever lain awake at 2 AM in the morning , replaying a decision you made years ago? A harsh word, a missed chance, a moment you wish you could walk back into and redo? That feeling has a name — regret, and it is one of the most universal experiences of being human.
But three very different traditions of thought — a 19th-century Danish philosopher, a 20th-century British thinker, and thousands of years of Eastern wisdom — converge on the same surprising insight: the "you" doing the regretting is not the same "you" who made the choice. Understanding why this is true can change your entire relationship with your past.
Part 1 — Western philosophy
Kierkegaard — you were actually there, and that matters
Søren Kierkegaard, the Danish philosopher, believed that the self is not something you are born with — it is something you build through your choices. Think of it like this: every time you make a real decision — not just picking lunch, but choosing who to be — you are constructing yourself.
This makes regret valuable, not shameful. Regret means you recognise that you were free. A person who drifts through life making no real choices cannot truly regret anything. Regret is the proof that at some moment, you showed up as a real person with real agency. Kierkegaard would say: honour that. Do not run from the sting of regret; it is your conscience doing its job.
"Regret is not a sign of weakness. It is the proof that you were present and genuinely free."Watch · under 1 minute Every decision is a path to regret — Søren Kierkegaard
But Kierkegaard also knew that the self changes. A person who goes through grief, joy, failure, or spiritual growth is not the same configuration they were before. So while the person who acted was genuinely you, the person looking back may already be someone else. Which leads to the next question…
The Ship of Theseus — are you still you?
Here is a puzzle from ancient Greece. Theseus, the hero who slew the Minotaur, sailed home on a wooden ship. Over the years, every plank of that ship rotted and was replaced — one by one, until nothing of the original wood remained. The question the Greeks asked: is it still the same ship?
Now apply that to yourself. The cells in your body are largely replaced every few years. The beliefs that drove your worst decision have probably shifted. The relationships that gave that moment its meaning have transformed. The version of you from ten years ago held different fears, different knowledge, different habits. Plank by plank, you have been rebuilt.
So when you torture yourself over something "you" did years ago — are you even the same ship?
Watch · 60 seconds The Ship of Theseus paradox explained
Parfit — identity is a matter of degree, not a fixed fact
Derek Parfit, the British philosopher, went further than anyone before him in challenging our assumptions about the self. His central argument, in plain terms, is this: there is no deep fixed "you" that travels through time like a coin in a pocket. What we call the self is really a flowing chain of memories, beliefs, intentions, and habits. And that chain gets thinner the further back you go.
The you of today shares many memories and values with the you of five years ago — the chain is fairly strong. But the you of twenty years ago? That chain is much weaker. You have different beliefs, different priorities, a different understanding of the world. Parfit would say: the connection is real, but it is not the rock-solid identity we assume it is.
What connects you to your past self is like a chain — real, but with links that grow thinner over time.
Watch · short interview clip Derek Parfit on personal identity, in his own words
This does not mean we abandon responsibility. We still have obligations toward others we have wronged, and we should absolutely make amends where we can. But it does mean that punishing yourself endlessly for who you were is philosophically shaky. You are not fully the same person. The evidence is all around you.
Kierkegaard : The self is built through choices. Regret proves you were genuinely free. Ship of Theseus: If every plank is replaced, is it the same ship? If you have changed, are you the same person? Parfit: Identity is a chain of overlapping connections — not a single, fixed thing.
Part 2 — Eastern Wisdom
The river — a more alive metaphor
Long before Western philosophers were debating ships and psychological chains, Indian philosophy — in early Buddhist thought and the Upanishads — was using a far more beautiful image for the self: a flowing river.
Stand on the bank of the Ganges or the Yamuna. You look down and say, "There is the river." You give it a name. But what are you actually seeing? The water in front of you right now is entirely different from the water that was there a moment ago. New drops arrive every second from distant mountains. The mud shifts, the current changes. The river is not a thing — it is a continuous process of becoming.
The ancient saying captures it perfectly: you can never step into the same river twice. The second time you step in, it is not the same water. And, crucially, you are not quite the same person either.
Watch · short explainer Khan Academy — identity, change, and impermanence
Setting the water free
Here is the most powerful image in this whole conversation. Regret is what happens when you reach upstream, fill a bucket with the muddy water from five miles back, and insist on carrying it with you as you flow forward.
The version of you that made that mistake years ago was a specific bend in the river — shaped by the exact rocks, terrain, and conditions of that particular time and place. The bend looked the way it did because of those circumstances. That water has long since flowed into the ocean. The rocks have shifted. The bend itself has changed shape.
You cannot go back and fix the water that has already flowed past. That is simply not how rivers work. But here is what Indian philosophy gently invites you to notice: right now, in this present moment, the water flowing through you is fresh. It is clear. It is perfectly capable of carving a brand new path through the mountains ahead.
You do not need permission to flow forward. That is just what rivers do.
Bringing it all together
Four very different voices — Kierkegaard, Parfit, the ancient Ship paradox, and the river wisdom of Indian philosophy — converge on a single, liveable truth:
The takeaway :
Acknowledge what you did. Learn what you can from it. Make amends where you still can. And then recognise, with honesty rather than self-deception, that the person who made that choice and the person now carrying the regret are connected — but not identical. The chain exists. The river is the same river. But the water is new. You have already changed more than you know. Stop carrying the bucket from upstream. Let it go. Flow forward.
Kierkegaard would call this the courage of the spirit. Parfit would call it a healthy reduction of the burden of personal identity. The Ship of Theseus just keeps sailing. And the Ganges — the Yamuna — every river that has ever been given a name — simply keeps moving toward the sea, indifferent to the bends it has already rounded, fully alive in the water it carries right now.