What is it like to be a bat?

Ethics Explainer: What is it like to be a bat?

“What is it like to be a bat?” is the intriguing question philosopher Thomas Nagel asks in his 1974 article, first published in The Philosophical Review.

Nagel’s argument goes something like this:

“We can imagine what it might be like to be nocturnal, to have webbing on our arms, to be able to fly, to have poor vision and perceive the world through high frequency sound signals, and to spend our time hanging upside down.”

“But even if we can imagine all of these things, it only tells us what it is like for me to be a bat, or for me to behave as a bat behaves. It does not tell us what it is like for a bat to be a bat.”

More than meets the eye

Is Nagel correct?

Nagel is pointing out that there is a subjective character of conscious experience that is not captured by physical descriptions of the brain or observable behaviours. He is taking issue with the reductive materialist or physicalist account that denies the so called gap between ‘mind’ and brain in the mind-body problem.

The mind-body problem comes about because we often subjectively feel as though our mind, with which we often identify the most, is somehow so much more than just our physical brain. Our mind sometimes also feels separable (even if not detached) from our body!

For example, we may forget that we are sitting on a bus, riding to work, and instead be transported back to an earlier time through the use of our memory. There is also the sense that my experiences are truly unique to me, and no one else can understand them in quite the same way.

The materialist denies the gap between mind and brain by arguing that the mind and consciousness is explainable entirely by physical processes. This position they defend is known as monism, and stands in contrast to dualism.

Note that René Descartes was a Dualist, due to his account of mind and body as two different substances. He equated the mind with the soul – an immaterial substance.

Mind over matter?

While Nagel is not committed to dualism, he claims that physicalism, if it is to be convincing, needs to account for both objective and subjective experience. Both are required to understand the mind-body problem. He contends, “Without consciousness the mind-body problem would be much less interesting. With consciousness it seems hopeless’”!

Nagel doesn’t think we can easily explain consciousness by simply describing a person or animal’s experience or set of behaviours.

This raises the troubling question: if I cannot embody a particular perspective, for instance, I cannot actually be anyone other than myself, then how can I truly understand it?

How can I ever know what it is like to be a bat, a dog, a cat, a horse, or even another person? Can I only ever truly understand what it is like to be me?

Nagel highlights the fact that there’s something mysterious about consciousness that cannot simply be explained away.

Nagel’s argument has been met with criticism. Daniel Dennett is one such critic, even while acknowledging this paper as “The most widely cited and influential thought experiment about consciousness”.

Dennett denies Nagel’s claim that the bat’s consciousness is inaccessible. He says the most important features of a bat’s consciousness would be accessible in some way to third person (that is, ‘objective’ or empirical) observation. In this way, information about what it is like to be a bat could be gleaned using scientific experiments.


Does it feel the same to you?

Yet this thought experiment still captures the imagination and plays on our fears of existing in a solipsistic universe. With our desire to be understood, we want to know that others understand what it is like for us, and, similarly, we them.

Plus, we can go further. With the development of artificial intelligence (AI), how can we know when a computer becomes conscious? And if it is conscious, could we understand what that is like?

Isn’t this important if we develop conscious robots who could be harmed by what we require of them (for example, to fight in wars)?

More simply, if you have ever wondered whether the sky you see as blue is the same experience had by your friend (assuming they are not colour blind), or whether the sweet strawberry tastes the same to your partner, then you are playing with this idea of subjective conscious experience.

Can we ever truly know what it is like for someone or something else?

Ethics Explainer: Plato's Cave

Plato’s allegory of the cave is a classical philosophical thought experiment designed to probe our intuitions about epistemology – the study of knowledge.

This story offers the reader an insight into one of Plato’s central concepts, namely, that eternal and unchanging ideas exist in an intellectual realm which we can only access through pure Reason.

Western philosophy may be traced back to Ancient Greece. We have a record of Socrates’ (469-399 BCE) oral teachings through the writings of his student, Plato (427-347 BCE). In these Socratic Dialogues, Socrates argues with his interlocutors in an effort to seek truth, meaning, and knowledge. Plato’s Republic is the best known of these and, in book VII, Socrates presents Glaucon (Plato’s older brother) with an unusual image:

Imagine a number of people living in an underground cave, which has an entrance that opens towards the daylight. The people have been in this dwelling since childhood, shackled by the legs and neck, such that they cannot move nor turn their heads to look around. There is a fire behind them, and between these prisoners and the fire, there is a low wall.

Rather like a shadow puppet play, objects are carried before the fire, from behind the low wall, casting shadows on the wall of the cave for the prisoners to see. Those carrying the objects may be talking, or making noises, or they may be silent. What might the prisoners make of these shadows, of the noises, when they can never turn their heads to see the objects or what is behind them? 

Socrates and Glaucon agree that the prisoners would believe the shadows are making the sounds they hear. They imagine the prisoners playing games that include naming and identifying the shadows as objects – such as a book, for instance – when its corresponding shadow flickers against the cave wall. But the only experience of a ‘book’ that these people have is its shadow.

After suggesting that these prisoners are much like us – like all human beings – the narrative continues. Socrates tells of one prisoner being unshackled and released, turning to see the low wall, the objects that cast the shadows, the source of the noises as well as the fire.

While the prisoner’s eyes would take some time to adjust, it is imagined that they now feel they have a better understanding of what was causing the shadows, the noises, and they may feel superior to the other prisoners.

This first stage of freedom is further enhanced as the former prisoner leaves the cave (they must be forced, as they do not wish to leave that which they know), initially painfully blinded by the bright light of the sun.

The liberated one stumbles around, looking firstly only at reflections of things, such as in the water, then at the flowers and trees themselves, and, eventually, at the sun. They would feel as though they now have an even better understanding of the world.

Yet, if this same person returned to the dimly lit cave, they would struggle to see what they previously took for granted as all that existed. They may no longer be any good at the game of guessing what the shadows were – because they are only pale imitations of actual objects in the world.

The other prisoners may pity them, thinking they have lost rather than gained knowledge. If this free individual tried to tell the other prisoners of what they had seen, would they be believed? Could they ever return to be like the others?

The remaining prisoners certainly would not wish to be like the individual who returned, suddenly not knowing anything about the shadows on the cave wall!

Socrates concludes that the prisoners would surely try to kill one who tried to release them, forcing them into the painful, glaring sun, talking of such things that had never been seen or experienced by those in the cave.



Interpreting the Allegory of the Cave

There are multiple readings of this allegory. The text demonstrates that the Idea of the Good (Plato capitalises these concepts in order to elevate their significance and refer to the idea in itself rather than any one particular instantiation of that concept), which we are all seeking, is only grasped with much effort.

Our initial experience is only of the good as reflected in an earthly, embodied manner. It is only by reflecting on these instantiations of what we see to be good, that we can start to consider what may be good in itself. The closest we can come to truly understanding such Forms (the name he gives these concepts), is through our intellect.

Human beings are aiming at the Good, which Medieval philosophers and theologians equated with God, but working out what the good life consists of is not easy! Plato claims each Soul (or mind) chooses what is good, saying:

 “But, whether true or false, my opinion is that in the world of knowledge the idea of good appears last of all, and is seen only with an effort.”

Ethics Explainer: The Turing Test

Much was made of a recent video of Duplex – Google’s talking AI – calling up a hair salon to make a reservation. The AI’s way of speaking was uncannily human, even pausing at moments to say “um”.

Some suggested Duplex had managed to pass the Turing test, a standard for machine intelligence that was developed by Alan Turing in the middle of the 20th century. But what exactly is the story behind this test and why are people still using it to judge the success of cutting edge algorithms?

Mechanical brains and emotional humans

In the late 1940s, when the first digital computers had just been built, a debate took place about whether these new “universal machines” could think. While pioneering computer scientists like Alan Turing and John von Neumann believed that their machines were “mechanical brains”, others felt that there was an essential difference between human thought and computer calculation.

Sir Geoffrey Jefferson, a prominent brain surgeon of the time, argued that while a computer could simulate intelligence, it would always be lacking:

“No mechanism could feel … pleasure at its successes, grief when its valves fuse, be warmed by flattery, be made miserable by its mistakes, be charmed by sex, be angry or miserable when it cannot get what it wants.”

In a radio interview a few weeks later, Turing responded to Jefferson’s claim by arguing that as computers become more intelligent, people like him would take a “grain of comfort, in the form of a statement that some particularly human characteristic could never be imitated by a machine.”

The following year, Turing wrote a paper called ‘Computing Machinery and Intelligence’ in which he devised a simple method by which to test whether machines can think.

The test was a proposed a situation in which a human judge talks to both a computer and a human through a screen. The judge cannot see the computer or the human but can ask them questions via the computer. Based on the answers alone, the human judge had to determine which is which. If the computer was able to fool 30 percent of judges that it was human, then the computer was said to have passed the test.

Turing claimed that he intended for the test to be a conversation stopper, a way of preventing endless metaphysical speculation about the essence of our humanity by positing that intelligence is just a type of behaviour, not an internal quality. In other words, intelligence is as intelligence does, regardless of whether it done by machine or human.

Does Google Duplex pass?

Well, yes and no. In Google’s video, it is obvious that the person taking the call believes they are talking to human. So, it does satisfy this criterion. But an important thing about Turing’s original test was that to pass, the computer had to be able to speak about all topics convincingly, not just one.



In fact, in Turing’s paper, he plays out an imaginary conversation with an advanced future computer and human judge, with the judge asking questions and the computer providing answers:

Q: Please write me a sonnet on the subject of the Forth Bridge.

A: Count me out on this one. I never could write poetry.

Q: Add 34957 to 70764.

A: (Pause about 30 seconds and then give as answer) 105621.

Q Do you play chess?

A: Yes.

Q: I have K at my K1, and no other pieces. You have only K at K6 and R at R1. It is your move. What do you play?

A: (After a pause of 15 seconds) R-R8 mate.

The point Turing is making here is that a truly smart machine has to have general intelligence in a number of different areas of human interest. As it stands, Google’s Duplex is good within the limited domain of making a reservation but would probably not be able to do much beyond this unless reprogrammed.

The boundaries around the human

While Turing intended for his test to be a conversation stopper for questions of machine intelligence, it has had the opposite effect, fuelling half a century of debate about what the test means, whether it is a good measure of intelligence, or if it should still be used as a standard.

Most experts have come to agree, over time, that the Turing test is not a good way to prove machine intelligence, as the constraints of the test can easily be gamed, as was the case with the bot Eugene Goostman, who allegedly passed the test a few years ago.

But the Turing test is nevertheless still considered a powerful philosophical tool to re-evaluate the boundaries around what we consider normal and human. In his time, Turing used his test as a way to demonstrate how people like Jefferson would never be willing to accept a machine as being intelligence not because it couldn’t act intelligently, but because wasn’t “like us”.

Turing’s desire to test boundaries around what was considered “normal” in his time perhaps sprung from his own persecution as a gay man. Despite being a war hero, he was persecuted for his homosexuality, and convicted in 1952 for sleeping with another man. He was punished with chemical castration and eventually took his own life.

During these final years, the relationship between machine intelligence and his own sexuality became interconnected in Turing’s mind. He was concerned the same bigotry and fear that hounded his life would ruin future relationships between humans and intelligent computers. A year before he took his life he wrote the following letter to a friend:

“I’m afraid that the following syllogism may be used by some in the future.

Turing believes machines think

Turing lies with men

Therefore machines do not think

– Yours in distress,


Ethics Explainer: The Sunlight Test

You can use the sunlight test by asking yourself, would I do the same thing if I knew my actions would end up on the front page of the newspaper tomorrow?

It’s an easy way to test an ethical decision before you act on it.

This test is most useful as a guard against moral temptations – where we stand to gain a great deal for doing something unethical. Moral temptations are strongest when the likelihood of punishment is low and what you stand to gain outweighs the ethical costs of doing the wrong thing.

Here’s a quick example

Say you have the chance to lie to your employer about a lunch you just took. It was meant to be with a client, but they cancelled at the last minute. You were already at the restaurant and ran into some friends and spent a couple of hours together.

If there’s not much chance of getting caught, do you tell your boss you were at a work lunch and charge the bill back to the company, or be honest and accept getting in a bit of trouble for taking an extended break?

This is a situation where the sunlight test can be really helpful. By taking the belief that we won’t get caught out of the equation, we’re able to determine whether our actions would stand up to public scrutiny.

It’s a really good way of ensuring we’re being motivated by what we think is good or right, and not by self-interest.

But what if I definitely won’t get caught?

The sunlight test is not actually about whether or not you’ll get busted. Often, it’s best used when it’s unlikely we’ll get caught doing the wrong thing. What we need to examine is whether a well informed but impartial third party would believe what we were doing is okay.

Although the sunlight test can be used by any person, it’s especially important for people whose professional roles put them in positions of public scrutiny – politicians, police, judges, journalists, and so on. For these people there is a real possibility their actions will end up on the front of the newspaper.

This means the sunlight test should be a daily part of their decision making.

However, even though there is a chance they’ll end up in the news, it’s still crucial public figures do what they believe is right. The sunlight test doesn’t ask us to imagine what the most popular course of action would be, but how our actions would be perceived by a reasonable and fair minded third party.