In What Does It All Mean? Thomas Nagel explores nine questions that philosophers have been trying to answer for thousands of years. Nagel believes that engaging with these questions directly is the best way to start a study of philosophy. He introduces the beginning philosopher to the questions and the most common arguments about them. Within his discussion, Nagel also inserts his own stand on the problems but cautions the reader not to rely on his conclusions. Instead, he repeatedly encourages the reader to think through the questions using her own reasoning.

Chapter One: Introduction

Chapter Summary: Philosophy is best studied by engaging with the philosophical questions first before anything else.

Begin your study of philosophy by thinking about the questions directly. Examine some possible solutions and look for their pitfalls. Do this and you will be in a better position to read the works of others.
Philosophy is different from science or mathematics because it does not rely on experiments or formal methods of proof.
The main concern of philosophy is to question and understand the very common ideas that we take for granted.
Philosophy can be difficult because the more basic the ideas one is trying to investigate, the fewer the available tools. A philosopher cannot assume too much. A philosopher can’t take things for granted.

Chapter Two: How Do We Know Anything?

Chapter Summary: To solve the problem of how you know anything, ponder on (1) whether there is really a physical world outside your mind or if your mind is the only thing that exists, and (2) consider whether or not it is all right to go on believing on an external world even if it does not exist.

The inside of your own mind is the only thing you can be sure of.
To conclude that a physical world outside your mind because you “sense” it is a weak proposition. Trying to prove the reliability of your senses by appealing to your senses is circular reasoning.
Ponder on this: What if all your experiences are just a giant dream with no external world outside it?
If the “giant dream” exists, then any evidence you use to prove that there is a physical world outside your mind will just really be part of the “giant dream.”
All evidence about what could be an outside world should come through your mind.
Ponder on this: Maybe, there is no physical world outside your mind. Maybe, only you, the subject of experience, is the one that exists.
“Solipsism” is the view that your mind is the only thing that exists.
Solipsism is a conclusion that is more than the evidence warrants.
Thomas Nagel’s position: “You don’t know anything beyond your impressions and experiences.” This position is also called “skepticism.”
A stronger form of skepticism proposes that you can’t be sure that you existed in the past because all you have to go on are the present contents of your mind.
Argument: “There is a physical world outside your mind because your internal experiences have external causes.” Skeptic’s answer: “Even if external causes exist, they cannot be observed directly. They have to go through the mind. How can you be sure about their properties and existence?”
Science doesn’t hold the final answer to whether or not there is a physical world outside your mind. Science relies on observation through the senses. If we can’t establish the reliability of our senses, we can’t establish the reliability of science.
Verificationism is the belief that without the possibility of a correct view of how things are, the thought that one’s impressions are not true is meaningless.
According to verificationism, if a physical world outside your mind does not exist, then what seems to be an illusion is actually perceptions of reality. Verificationism requires that reality is what we can observe.
“Egocentric predicament” is the problem of not being able to see reality as it is because of being trapped inside one’s mind.
It is difficult to escape our acceptance of the existence of a physical world outside our minds.

Chapter Three: Other Minds

Chapter Summary: To solve the problem of whether or not other minds exist, (1) explore what you can really know beyond the contents of your mind, and (2) consider the possibility that there might be much less or much more conscious life than you assume.

The only experience you can actually have is your own.
Your belief that other people have their own experiences is based on your observation of their behavior. You can’t enter their minds and experience it yourself.
It is uncertain whether two human beings could have the same exact experience.
Physical differences and other factors may contribute to differences in experience.
The differences in sensual experiences among human beings may or may not be radical. We can’t know 100%.
The experiences of human beings could be entirely different among each other.
Radical conclusion: Because you can’t experience other people’s mental lives directly, it is plausible to conclude that other minds do not exist.
If other minds do not exist, their physical behavior is caused by physical factors.
You can’t be sure 100% that other minds exist just because other people act and talk. You don’t see the connection between other people’s inner experience and their behavior “directly.”
To “immediately” believe that other minds exist just because it “seems” obvious is to rely on instinct, not knowledge.
If you accept that there are other people who have minds, you should be ready to accept that animals, plants, cells, nonliving things, and even machines “could” have minds too.
The only way you can be sure that other people, other organisms, and other things have minds is to observe “directly” the correlations between their internal experience and their physical manifestations. Since we don’t have any capability to observe these correlations “directly,” we can’t be 100% sure about the presence or the absence of other minds.

Chapter Four: The Mind-Body Problem

Chapter Summary: There seem to be two states happening within a person: mental states and physical states. How these states interact and whether or not they are mutually exclusive is a problem that has bothered philosophers for thousands of years.

What happens to the mind seems to depend on what happens to the body.
Ponder this: Is your mind something different from your brain, though connected to it? Or is it part of your brain?
The mind is different from the brain because brain processes can be observed by an outsider but the mind (feelings, sensations, experiences) cannot be observed by the same outsider.
If the contents of the mind cannot be observed by an outsider in a way that she can observe the contents of the brain, then the mind cannot be a “physical” part or state of the brain.
“Dualism” is the view that a person is made up of two substances: matter and mind. Another way to put this is that a person has a body and a soul.
“Physicalism” also known as “materialism” is the view that a person consists of noting but physical matter. Therefore, the mind and its contents are simply physical states of the brain. There is only the body, there is no soul.
“Dual aspect theory” is an alternative to both dualism and physicalism. It is the view that a brain is an object with both physical and mental properties.
Mental states can’t simply be explained by purely physical causes and effects. Mental states “feel” a certain way that is different from a physical phenomenon.
Thomas Nagel’s position: There is a physical reality that people can observe from the outside. There is a mental reality that individuals experience from the inside. This mental reality could also occur to other organisms.
To have a purely physical theory about the mind and the body, and therefore the entire universe, the mind or consciousness has to be identified with some physical state.
So far, it is impossible to have a unified physical theory of the universe because arguments against it are strong enough to refute it.

Chapter Five: The Meaning of Words

Chapter Summary: Words allow us to understand the universe, communicate with each other, and invent things. But it is a mystery how words have this incredible power.

There is no resemblance between a word and its referent. The relationship of a word to its referent is indirect.
But you cannot understand a word by itself. In order to understand a word, you need to see or know its referent.
We use other words to give a word meaning, a definition. But this could be circular reasoning. We need to get to some words that have “direct meanings.”
What is unusual with a word is that when you use it both in written or oral form, it refers to all the samples of its referent in the past, present, and the future. It refers to all its possible uses, both true and false.
Behind a word is a concept, a mental picture of what the word represents. This raises new problems because the word refers to both “the object” and “the concept of that object.”
The problem with a word’s meaning is that it is not located anywhere, not in the word, in the mind, or in the concept.
The social phenomenon of language does not fully explain the universal meaning of words.

Chapter Six: Free Will

Chapter Summary: To solve the problem of whether or not free will exists, (1) explain what you mean when you say you could have done something other than what you did, and (2) explain what you and the world would have to be like for this to be true.

Determinism is the view that existing laws of nature create series of circumstances that make the actions that people take inevitable, ruling out other possibilities.
If determinism is true, it implies that people should not be held responsible for their actions, because they did not choose them.
Some people argue that even if determinism is true, it is still practical to praise people for doing good and to punish them for doing bad.
Some scientists argue that because there’s more than one thing an electron may do at any given moment, determinism is false.
If determinism is incorrect, then free will definitely exist, and people should be held responsible for their actions.
For free will to exist: (1) an actor determined her action by doing it, (2) her action was not determined in advance, (3) her action did not just happen, and (4) she could have done the opposite.
Ponder this: You are made up of your desires, beliefs, personality, and the circumstances that created who you are. If an action that you performed is absent of all these forces, could we conclude that “you” really did it?
If free will is true and choices are not determined by forces and circumstances within your life, then you could not have done what you did. You could not be held responsible for your actions.
If free will exists, then it is plausible that things just happen with no reason.
Whether or not determinism is true, it is still plausible that we are not responsible for our actions. If determinism is true, antecedent circumstances are responsible. If determinism is false, nothing is responsible.
To claim that the existence of free will implies that things just happen with no reason is meaningless. Free will is just a basic feature of the world and cannot be analyzed.
Thomas Nagel’s position: If everything that people did was determined then they are essentially trapped. They could not be held responsible for their actions.

Chapter Seven: Right and Wrong

Chapter Summary: The biggest problem in ethics and morality is whether or not there is a universal standard for them. Given that humans act according to their motives and that motives are innumerable, a single standard for ethical behavior seems farfetched.

Not all “lawful” acts are necessarily “right” acts.
Thoughts about the wrongness of certain behaviors are based on a concern to the effect of one’s actions on people in general.
Ponder this: If you can get what you want by doing something considered to be wrong, why shouldn’t you?
Most religious motivations to ethical behavior identify something that a person should care about (God), and then connect morality to it.
An objection to using God as the ultimate motivation to refrain from doing bad is that even if God exists and forbids what is wrong, his forbidding isn’t what makes the act wrong. The act is wrong and that is why God forbids it.
There is no substitute for a direct concern for other people as the basis of moral behavior.
The problem with morality is that it is supposed to apply to everyone, and yet not everyone has a concern for other people and those who care about other people only care about those they know, not everyone.
The universality of morality is questioned when we compare the motives of different individuals and societies at different times.
The most radical form of moral relativism claims that the most basic standards of right and wrong depend entirely on the social and cultural conventions.
Thomas Nagel’s position: Relativism is problematic because it always seems possible to criticize the accepted standards of any society. However, to criticize a society’s moral code means to appeal to a more objective standard, which itself is unclear.
The most foundational question about morality is how universal and objective it is.
The problem with moral arguments is that they appeal to a capacity for impartial motivation which is supposed to be present in all of us but seems deeply buried.
It is difficult to justify morality because people have so many motives behind their actions.

Chapter Eight: Justice

Chapter Summary: To tackle the problem of inequality and justice, (1) identify which causes of inequalities are morally wrong, and (2) determine which methods of interfering with these inequalities are morally right.

There are two kinds of inequalities: one that is deliberately imposed and one that is accidental.
Deliberately imposed inequality—like racial and gender discrimination—is self-evidently wrong because the discriminator is doing something wrong. The remedy is simply to prevent it.
To analyze whether or not inequalities caused by luck are really wrong is a more difficult philosophical question.
Ponder this: “Are those people who were born in rich families by luck really at fault to inequalities in a competitive social system? Is it wrong for people to accumulate wealth to better the lives of their families? Is it right to take money away from rich people to give to those who were born in poor families also by luck?”
Two main sources of accidental inequalities in a competitive social system are: (1) differences in socioeconomic classes into which people are born, and (2) differences in natural abilities and talents.
To remedy accidental inequalities caused by differences in socioeconomic classes, either: (1) interfere with the causes or (2) interfere with inequalities directly.
Interfering with the causes of accidental inequalities is problematic because these are relatively innocent choices arising from a motive to improve one’s state in life.
It is easier to interfere with the inequalities directly but doing so does not remove the inequalities permanently. This is usually done by taking money from the rich through various forms of taxation and giving that money to the poor in the form of welfare programs.
There is not much we can do to eradicate inequalities based on talent if we do not abolish the competitive social system itself. While this could solve the inequalities, it will incur heavy costs on freedom and efficiency.
People who are against redistributive taxation argue that economic transactions that produce inequalities are not inherently wrong and that it isn’t right for governments to interfere on people who aren’t deliberately hurting anyone.
Thomas Nagel’s position: Both deliberately imposed and accidental inequalities are unfair. We need redistributive taxation and social welfare programs.
The problem of “global inequality and justice” is problematic just because there is no world government to regulate transactions among nations and such a government would probably be a bad government.

Chapter Nine: Death

Chapter Summary: Two important philosophical questions concerning death are: (1) “What happens when we die?” and (2) “Is dying a bad thing or a good thing?”

The question of survival after death is related to the mind-body problem.
For dualists, the soul could exist on its own even without the body so it continues its mental life after death.
People who reject the dualist view on death argue that the soul seems to depend entirely on the body for its continued existence.
For physicalists, life after death is impossible because physical death means mental death.
Thomas Nagel’s position: Ordinary observation should be enough to convince us that there is no life after death. Consciousness is intricately dependent on our nervous system.
Ponder this: “Is your death a good thing or a bad thing? We accept that there was a time before we were born when we didn’t yet exist, so why are we bothered about the prospect of not existing again at death?”
There are three plausible answers to the question above: (1) Death is neutral because nonexistence can’t be good or bad; (2) Death is bad because nonexistence is the ultimate evil; and (3) Death is good because it is boring to live forever.
Logically, we should only fear death if we will survive it.

Chapter Ten: The Meaning of Life

Chapter Summary: For one’s life to have meaning, it has to be part of something bigger than itself. But to follow this line of reasoning could lead to the conclusion that life is pointless after all.

We can’t live forever so we can only find the meaning of life within life itself.
Ponder this: “There are justifications for the little things that we do. But is there really a point in our life as a whole?”
For our life to have meaning, it has to be part of something larger.
But we can ask the question again: “What is the meaning of that ‘larger thing?‘”
Some people point to this ‘larger thing’ as God or another “ultimate explanation.” But this does not satisfy the questions.
Questions about the meaning of the “ultimate explanation” can continue ad infinitum. This leads to a painful logical conclusion: that life has no meaning after all.
Even if life is inherently meaningless, it is still useful to accept the belief that what one does matters.

Vince Imbat

What Does It All Mean? by Thomas Nagel (Book Summary)