What Is It Like to Be a Bat? Thomas Nagel and the Limits of Objectivity

Having read several books about consciousness in 2025, I kept encountering references to Thomas Nagel’s What Is It Like to Be a Bat?. And really, who would not want to read something with a title like that?

The piece itself is brief. The original paper appeared in The Philosophical Review in October 1974 and runs to only sixteen pages. Its influence far outweighs its length.

Cover image: What Is It Like to Be a Bat? by Thomas Nagel, fiftieth-anniversary edition published by Oxford University Press. Used here for purposes of review and commentary.

The Question Behind the Bat

Nagel begins from a deceptively simple proposal: an organism is conscious when “there is something it is like” to be that organism. Consciousness is not merely the ability to react, process information or display intelligent behaviour. It includes how existence feels from the organism’s own point of view.

Bats make the problem unusually vivid. They are mammals, close enough to us that most people readily accept that they have experiences. Yet many bats navigate primarily through echolocation, extracting distance, shape, motion and texture from reflected high-frequency sounds.

We can study how this system works. We can map the relevant anatomy, measure the sound pulses and observe the neural processing involved. We can even imagine ourselves with webbed arms, poor vision and a sonar-like sense.

But imagining what it would be like for a human to behave as a bat behaves is not the same as understanding what it is like for a bat to be a bat. Our imagination works with material drawn from our own senses and experiences. We can construct analogies, but the result remains organised around a human point of view.

Nagel does not quite claim that all understanding across species is impossible. Partial approximation may be possible, especially between creatures whose forms of experience overlap. His deeper point is that experience is inseparable from a perspective. The further we are from the relevant perspective, the less completely we can understand its subjective character.

A Challenge to Materialism, Not a Refutation

This creates a distinctive problem for reductive materialism. Scientific explanation normally advances by becoming less dependent on any particular observer. Lightning can be described as an electrical discharge without reproducing the visual experience of seeing a flash across the sky.

Consciousness appears to resist the same move. The subjective point of view is not merely an appearance that can be stripped away to reveal the real phenomenon underneath. It is part of the phenomenon that needs explaining.

An objective theory may describe what the nervous system does, how information is processed and which brain states accompany a particular experience. But if the theory says nothing about why undergoing those processes feels like anything from the inside, Nagel argues that an essential part of consciousness remains outside the explanation.

This is a serious obstacle for materialism, but it is not a demonstration that materialism is false. Nagel is careful about that distinction. His claim is that the physicalist explanations available to us do not yet provide a conception of how subjective experience could be identical with an objective physical process.

A future theory might do better. The difficulty is that we do not currently know what such a theory would need to look like. The problem may lie less in the existence of consciousness than in the conceptual tools with which we are attempting to describe it.

I have long leaned towards materialism, even before I knew the vocabulary for the position. The idea that minds arise from physical processes has always seemed more compelling to me than the alternatives.

Nagel does not persuade me to abandon that view. He does make it harder to treat materialism as though the central work had already been completed. Saying that consciousness comes from the brain is a statement of dependence. It is not yet an explanation of how physical activity becomes lived experience.

Why the Essay Still Matters

The paper also matters for how we think about nonhuman minds. Nagel does not offer an argument about animal-welfare policy, but he encourages a particular kind of humility. An animal’s inability to describe its experience in human terms does not show that no experience is present.

At the same time, recognising the limits of our perspective does not make scientific investigation pointless. Behaviour, anatomy and neurology can tell us a great deal about what animals perceive and how they respond. They may bring us closer to their forms of experience even if they cannot place us fully inside them.

Part of my fascination with consciousness probably began with science fiction. Jules Verne’s The Mysterious Island and Isaac Asimov’s Foundation novels were early favourites. Asimov’s psychic characters and, elsewhere, the apparent inner lives of his robots raised questions about how minds work, what counts as thinking and whether subjective experience might exist in beings unlike us.

Nagel’s essay endures because it refuses both an easy mystical answer and an easy scientific dismissal. It does not claim that consciousness must be nonphysical. It insists that any physical account worthy of being called complete must explain the subjective character of experience rather than quietly defining it out of existence.

The bat is memorable because it does not prove that matter cannot think. It asks what it would mean for matter to feel like anything at all.