When Life Gives You a Brain

We move through the world assuming our senses are in sync. Sight, sound, touch—they usually agree. But flip just one of them, and the whole system starts to wobble. That’s exactly what happens with prism goggles. This week, I revisit some classic experiments with inverting goggles. How does the brain adapt to conflicting signals? Does it rebuild an internal representation—or just adjust its predic...

We talk about meaning all the time — what things mean, what people mean, what life means. It feels obvious that meaning is something we have . Probably in the brain. Somewhere. Neuroscientists even talk that way. They say things like, “This part of the brain represents faces,” or “That spike means the person saw a dog.” But it’s not clear what “means” really means in this context. What is meaning?...

Most of us take it for granted that our thoughts have meaning. You can think about a dog, a holiday, or the square root of 144 — and somehow, your brain just gets it. Cognitive science has long explained this by saying the brain uses internal representations: mental models that stand in for things in the world. But not everyone agrees. Some researchers say we’ve got it backwards — that meaning doe...

We might mistake a garden hose for a snake. There’s no snake — just a brain responding to the wrong thing in the wrong way. But somehow, we still say the our brain represents a snake. Even though there is no snake. That sounds straightforward, until you ask what “represent” really means — and how a lump of neurons can be about anything. This is a public episode. If you would like to discuss this w...

When you see a dog , something happens in your brain. A pattern of activity fires, and somehow, that pattern feels like it means something. Cognitive scientists often say that your brain “represents” things — objects, ideas, emotions, and dogs. Representations is how we explain perception, memory, language, and thought. But not everyone agrees that this idea holds up. Some say the notion of repres...

We tend to think words get their meaning from the world. You see a dog, you learn the word “dog,” and now the word points to the thing. But large language models don’t see dogs. Or anything at all. They’ve learned only from text — just patterns of words predicting other words. This week, I wrote about what that means for AI, language, and us. It’s a deep dive into the grounding problem — a philoso...

Think about a sign. Or a symbol, an idea, a thought, a concept, or a representation. What kind of thing are you really thinking about? In 1972, NASA pinned a message to a spaceship, hoping one day an alien life form might find it and understand it. The plaque was full of symbols — diagrams, drawings, a raised human hand. Those symbols mean something to us. But only because we know they’re symbols...

We’ve all been chatting with machines lately — ChatGPT, Gemini, Claude — and they sound impressively human. It’s easy to wonder: do they just seem to understand, or is there something real going on inside? Back in 1980, philosopher John Searle argued that no matter how good a machine’s answers are, something crucial is missing. His Chinese Room thought experiment challenges the idea that smart pro...

Brains predict. LLMs predict. But does that mean they’re doing the same thing? A short essay on functions, intelligence, and the trouble with words. We used to think intelligence was all about reasoning. Then we said it was biological. Now we’re told it’s maybe... prediction? That shift raises a big question:If both brains and language models predict, does that mean they’re doing the same thing? T...

We know how to build things — houses, bridges, and bookshelves. And when we build, we follow instructions: blueprints and manuals. But living things don’t follow fixed instructions. They grow. And that might be a very different kind of thing. This essay is about what happens when we stop trying to build artificial brains — and we start trying to grow them. It’s about the difference between code th...

We like to think that if a system gets complex enough, consciousness just kicks in -- the lights turn on. It’s a neat idea — and it shows up everywhere, from neuroscience papers to AI hype. But the science isn’t nearly that simple. This essay asks: does consciousness really just come along for the ride when things get complicated? It looks at what the science actually says. If consciousness isn’t...

Complexity is all around us — in life, brains, weather, cities, economies... We know a brain is more complex than a rock, but good luck explaining why. Even scientists struggle to define it — we know it when we see it, but that’s about it. So what exactly makes something complex? This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, vis...

What if your conscious experience depends on the direction of time? This week I get speculative. Entropy is why cream swirls into coffee and eggs break — but never the other way around. Could that same arrow of time help explain why you have thoughts, memories, and a sense of self? This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, v...

Information isn't just an abstract concept—it has real, physical consequences. Physicists and engineers have long treated information in different ways: one as bits in a message, the other as something tied to the fundamental laws of nature. But Maxwell’s Demon, a thought experiment from the 19th century, revealed a strange connection between information and entropy, suggesting that processing inf...

The mind has puzzled thinkers for centuries—Descartes saw it as something separate from the body, while today, we tend to think of it as an information processor. Over time, our understanding has shifted, shaped by philosophy, psychology, and even breakthroughs in computing. But the question remains: is the mind just a biological machine crunching data, or is there something fundamental missing fr...

This week, I explore the puzzle of why we need special sciences when physics theoretically explains everything. I ask how different scientific disciplines like psychology and economics might discover things that can't be reduced to physics. I raise the controversial question of whether consciousness is more like money (functionally defined and multiply realisable) or more like jade (defined by wha...

Two coffee tasters at Maxwell House suddenly hate the coffee they once loved. One says he's just become more sophisticated, while the other insists his taste buds must be broken -- even though they're drinking the exact same coffee they've had for years. Philosopher Daniel Dennett uses their predicament to challenge something we all take for granted: that we have special, direct access to our own...

False memories are incredibly common, even for everyday experiences like driving. Scientists have found that not only can memories be easily manipulated, but our brains regularly reconstruct past events based on our current needs and circumstances. Here's the twist, though - what many consider a flaw in human memory might be a clever evolutionary feature that helps us adapt and learn without getti...

Memories aren't stored like files on a computer - they're constantly being rebuilt every time we remember them. Scientists have discovered ways to manipulate these reconstructions in mice, blocking memories from forming, erasing existing ones, and even creating artificial memories using light. But these techniques are still far from the kind of precise, selective memory manipulation we see in movi...

Our brains don't store memories like computers store files -- they recreate them every time we remember. When we recall something, different brain regions are involved in reconstructing the experience, combining sensory details, emotions, and context into what feels like a replay of the original event. But this means our memories aren't perfect copies -- they change slightly each time we recall th...

Mary's Room, a famous thought experiment, imagines a scientist who learns everything about colour while living in a black-and-white room but has never seen colour herself. For decades, philosophers have used this story to argue that science can't explain consciousness -- but what if science already knows exactly what would happen to Mary? Would Mary herself know that she could never see colour nor...

Some blind people can see using sound. They echolocate. When they do this, their visual cortex responds to sounds like it normally would for sight. Through stories of blind individuals who can ride bikes using sound and babies who learn to 'see' using specially designed glasses, this article takes us deep into questions about the nature of perception itself. What if seeing isn't really about havin...

For 50 years, Thomas Nagel's "What Is It Like to Be a Bat?" has been a key paper in discussions of consciousness. But have we misunderstood its central message? This deep dive challenges common interpretations of Nagel's work. It explores whether he's really arguing about knowledge limits, mind-body dualism, and science's ability to explain consciousness. Rather than just another analysis of bats...

This week, we’re discussing one of the most famous papers in philosophy: Thomas Nagel’s 1974 classic, What Is It Like to Be a Bat? Given how influential Nagel’s bat paper has been in the philosophy of mind and the cognitive sciences, it’s worth taking some time to understand it. So, this article starts a mini three-part series on Nagel’s ideas about bats. In Part 1 (that’s this article), we’ll foc...

Late one evening in July of 1797, a musket ball was fired through the air. Europe was ablaze with the French Revolutionary Wars, and the British Royal Navy was engaged in a daring raid on the Spanish island of Tenerife. Admiral Lord Horatio Nelson led the charge. As Nelson guided his men through the darkness, that fateful musket ball found its mark. It struck the Admiral’s right arm, shattering bo...