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Constructing the World
David Chalmers develops a picture of reality on which all truths can be derived from a limited class of basic truths. The picture is inspired by Rudolf Carnap's construction of the world in Der Logische Aufbau Der Welt. Carnap's Aufbau is often seen as a noble failure, but Chalmers argues that a version of the project can succeed. With the right basic elements and the right derivation relation, we can indeed construct the world. The focal point of Chalmers' project is scrutability: the thesis that ideal reasoning from a limited class of basic truths yields all truths about the world. Chalmers first argues for the scrutability thesis and then considers how small the base can be. The result is a framework in "metaphysical epistemology": epistemology in service of a global picture of the world. The scrutability framework has ramifications throughout philosophy. Using it, Chalmers defends a broadly Fregean approach to meaning, argues for an internalist approach to the contents of thought, and rebuts W.V. Quine's arguments against the analytic and the a priori. He also uses scrutability to analyze the unity of science, to defend a sort of conceptual metaphysics, and to mount a structuralist response to skepticism. Based on Chalmers's 2010 John Locke lectures, Constructing the World opens up debate on central philosophical issues concerning knowledge, language, mind, and reality.
494 pages, Hardcover
First published September 14, 2012
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About the author
David J. Chalmers
28 books528 followersDavid Chalmers is University Professor of Philosophy and Neural Science and codirector of the Center for Mind, Brain and Consciousness at New York University. He is the author of The Conscious Mind, The Character of Consciousness, and Constructing the World. He has given the John Locke Lectures and has been awarded the Jean Nicod Prize. He is known for formulating the “hard problem” of consciousness, which inspired Tom Stoppard’s play The Hard Problem, and for the idea of the “extended mind,” which says that the tools we use can become parts of our minds.
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Displaying 1 - 7 of 7 reviews
November 18, 2013
You can't avoid the consequences of diagonalization by adding premises.
October 5, 2019
This is an important thesis on epistemology (what can be known and how), by a prominent philosopher. It is extremely well-written and well-annotated. It includes copious footnotes, explanatory "excurses," a glossary, and a full index. The message is addressed to professional philosophers. The book is not meant to be accessible to the average reader. However, if you do enjoy reading philosophy and can manage logic and symbolic reasoning, you could skim the footnotes and probably get through it (as I did).
The question Chalmers addresses is whether or not some smallish set of facts and principles could account for (make understandable), every fact of the world. A lot of people believe this. It is a foundational principle of science.
In 1814, the French scientist-philosopher Laplace suggested that "given the right basic information, and sufficiently powerful reasoning, all truths about the universe can be determined" (Chalmers's paraphrase).
For example, if we had a complete book of physics, would it explain every other fact in the universe? Presumably, all of chemistry is ultimately explainable in terms of physical laws. We believe that biology is just a special and complex case of physics and chemistry. And the brain? That is just a chunk of biology, in principle understandable in terms of physics and chemistry. The mind? Same as the brain: in the end, it's physics. Cosmology? It's physics. And so on.
Chalmers's quest is not reductionistic. He is not looking to reduce all knowledge down to physics. His question and his goal are more abstract. He asks, do we have to study every single thing in the world in order to understand the world? Or are there some basic facts and principles that make the dizzying phenomena of the world understandable, or "scrutable," as he prefers to say?
Most people (including me) would agree that there must be a few basic facts and principle that explain large swathes of experienced things and events. It is not necessary to study every flea on every dog, every grain of sand. For example, the principles of aerodynamics help us understand why planes fly and why birds fly, and Frisbees, too. We don't need separate explanations for those. We can turn to basic principles of scrutability (understanding) to explain them all.
Chalmers asks: Is the scrutability hypothesis reasonable? And if it is, what would make a good set of basic principles? Would the laws of physics be enough? Or do you also need logic and mathematics to go with that, and maybe some psychological facts? What about how words get their meaning, because you need language to do science. What about the arts? That's a "thing" in the world. Can it be explained? What about feelings? How should we deal with uncertainty, errors and lies? Ghosts? What about meaning? In general, what basic things do we need to know in order to understand everything in the whole world?
Chalmers's project is an important one that gets to the heart of scientific knowledge. He takes Rudolph Carnap's failed attempt at a similar endeavor in the early twentieth-century as his starting point and builds out his own theory. Spoiler: Chalmers's answer is that we only need four kinds of information, abbreviated PQTI. That's right. If you knew just those four things, you would be able to understand everything in the universe!
Naturally, there is a caveat. Those four "things" are classes of knowledge. For example, P stands for Physics, meaning you would need to have a complete textbook of physics with principles and facts that accounted for all physical phenomena from stars to quarks. We do not have such a textbook. The other three categories are equally broad, but note: the list is not infinitely long. It has only four categories, and within each category, the principles of knowledge are a smaller set than the number of things they explain. Hence, Chalmers's scrutability program seems achievable in principle.
I remain totally unconvinced. Not of the scrutability hypothesis, which I buy, but of Chalmers's procedures, reasoning, and outcome. The problem is with his assumptions. Any theory has assumptions, and Chalmers does a valiant job of spelling out what his are. But he also has a ton of pre-theoretic assumptions "below the line." Those are the assumptions so basic they are not eligible for consideration or articulation. They are presupposed without even being named.
For example, Chalmers seems to presuppose realism. That is, the world exists as it appears, by and large. I have no doubt he would object to this claim. Not at all, he would say. I am open to anti-realist proposals if they can be made coherently. But in fact, as a practical matter of the text, he assumes that "truth" can be known "objectively," by "observation." None of those terms is defined. None appears in the book's glossary.
He also implies other "truths" about the world that involve atomism, individualism, hierarchical organization, and causal determinism, to name just a few assumptions, and "truths" about the mind and how it works, such as verification by observation, spontaneous analysis and synthesis, the relationship between sensation and perception, the nature of conceptualization, and many others. He seems blind to most phenomena of subjectivity such as self-reflection and creativity, intersubjectivity, and motivation.
I disagree with Chalmers's implicit pre-theoretic assumptions on nearly every count, so I was kicked off of his train of reasoning soon after it left the station. Nearly every argument in the book commits the logical error of assuming the consequent because of these hidden assumptions. I knew right away it was not a book for me. But I read it anyway. One always wants to know what the other side is thinking. (How can they live like that?)
My conclusion is that if you accept Chalmers's pre-theoretic assumptions about self, mind, and world, then you will find the book interesting and the arguments compelling. If not, you will see only a bizarre demonstration of pin-the-tail-on-the-donkey.
Chalmers, David J. (2012). Constructing the World. New York: Oxford University Press, paperback edition, 494 pp.
The question Chalmers addresses is whether or not some smallish set of facts and principles could account for (make understandable), every fact of the world. A lot of people believe this. It is a foundational principle of science.
In 1814, the French scientist-philosopher Laplace suggested that "given the right basic information, and sufficiently powerful reasoning, all truths about the universe can be determined" (Chalmers's paraphrase).
For example, if we had a complete book of physics, would it explain every other fact in the universe? Presumably, all of chemistry is ultimately explainable in terms of physical laws. We believe that biology is just a special and complex case of physics and chemistry. And the brain? That is just a chunk of biology, in principle understandable in terms of physics and chemistry. The mind? Same as the brain: in the end, it's physics. Cosmology? It's physics. And so on.
Chalmers's quest is not reductionistic. He is not looking to reduce all knowledge down to physics. His question and his goal are more abstract. He asks, do we have to study every single thing in the world in order to understand the world? Or are there some basic facts and principles that make the dizzying phenomena of the world understandable, or "scrutable," as he prefers to say?
Most people (including me) would agree that there must be a few basic facts and principle that explain large swathes of experienced things and events. It is not necessary to study every flea on every dog, every grain of sand. For example, the principles of aerodynamics help us understand why planes fly and why birds fly, and Frisbees, too. We don't need separate explanations for those. We can turn to basic principles of scrutability (understanding) to explain them all.
Chalmers asks: Is the scrutability hypothesis reasonable? And if it is, what would make a good set of basic principles? Would the laws of physics be enough? Or do you also need logic and mathematics to go with that, and maybe some psychological facts? What about how words get their meaning, because you need language to do science. What about the arts? That's a "thing" in the world. Can it be explained? What about feelings? How should we deal with uncertainty, errors and lies? Ghosts? What about meaning? In general, what basic things do we need to know in order to understand everything in the whole world?
Chalmers's project is an important one that gets to the heart of scientific knowledge. He takes Rudolph Carnap's failed attempt at a similar endeavor in the early twentieth-century as his starting point and builds out his own theory. Spoiler: Chalmers's answer is that we only need four kinds of information, abbreviated PQTI. That's right. If you knew just those four things, you would be able to understand everything in the universe!
Naturally, there is a caveat. Those four "things" are classes of knowledge. For example, P stands for Physics, meaning you would need to have a complete textbook of physics with principles and facts that accounted for all physical phenomena from stars to quarks. We do not have such a textbook. The other three categories are equally broad, but note: the list is not infinitely long. It has only four categories, and within each category, the principles of knowledge are a smaller set than the number of things they explain. Hence, Chalmers's scrutability program seems achievable in principle.
I remain totally unconvinced. Not of the scrutability hypothesis, which I buy, but of Chalmers's procedures, reasoning, and outcome. The problem is with his assumptions. Any theory has assumptions, and Chalmers does a valiant job of spelling out what his are. But he also has a ton of pre-theoretic assumptions "below the line." Those are the assumptions so basic they are not eligible for consideration or articulation. They are presupposed without even being named.
For example, Chalmers seems to presuppose realism. That is, the world exists as it appears, by and large. I have no doubt he would object to this claim. Not at all, he would say. I am open to anti-realist proposals if they can be made coherently. But in fact, as a practical matter of the text, he assumes that "truth" can be known "objectively," by "observation." None of those terms is defined. None appears in the book's glossary.
He also implies other "truths" about the world that involve atomism, individualism, hierarchical organization, and causal determinism, to name just a few assumptions, and "truths" about the mind and how it works, such as verification by observation, spontaneous analysis and synthesis, the relationship between sensation and perception, the nature of conceptualization, and many others. He seems blind to most phenomena of subjectivity such as self-reflection and creativity, intersubjectivity, and motivation.
I disagree with Chalmers's implicit pre-theoretic assumptions on nearly every count, so I was kicked off of his train of reasoning soon after it left the station. Nearly every argument in the book commits the logical error of assuming the consequent because of these hidden assumptions. I knew right away it was not a book for me. But I read it anyway. One always wants to know what the other side is thinking. (How can they live like that?)
My conclusion is that if you accept Chalmers's pre-theoretic assumptions about self, mind, and world, then you will find the book interesting and the arguments compelling. If not, you will see only a bizarre demonstration of pin-the-tail-on-the-donkey.
Chalmers, David J. (2012). Constructing the World. New York: Oxford University Press, paperback edition, 494 pp.
April 23, 2020
I think Chalmers is absolutely ingenious here--but like every philosophical project, it fails. It is an incredibly ambitious piece of work, that ranges across a variety of domains. Chalmers, as usual, remains incredibly and painstakingly careful, deliberate, and precise. This is the level of philosophy that everyone should aspire to, although it feels so awfully drawn out. I ended up drudging through this book from front to back simply to say that I did so.
The book is about a class of theses known as scrutability theses: the thesis that one can find all truths from a compact set of facts. If the scrutability thesis familiar, it is a project inspired by Carnap's Aufbau. As Chalmers puts it, his project can be seen as a form of Carnapian Rationalism.
Chalmers' main child is what he calls a priori scrutability. The thesis that from a compact set of facts, an agent can be in a position to know a priori that if C, then S, where Chalmers says that these compact set of facts is PQTI (the totality of physical and phenomenal facts with a That's All clause, and Indexicals). Carnap's Aufbau, on the other hand, used an entirely phenomenal and logical set of facts and attempted to use strict definitions rather than larger a priori relations.
Thus, Chalmers takes inspiration from Carnap's thesis, and does the following:
(1) Add much more to the base facts, and
(2) Weakens the relation that one can use.
The project is entirely epistemological, but Chalmers doesn't really attempt to be reductive in any other manner. He considers a large variety of these theses and defends a few of them. These theses become tools for Chalmers to construct and argue for the defense of other things. These theses first become tools that are used to define epistemically possible scenarios (by defining equivalence classes on the scrutable facts). Most notably to me, these scenarios are used to construct a kind of intension in a very Fregean manner. These intentions thereby help develop a kind of two-dimensional semantics (playing the role of the primary intension).
He also uses these defends structuralism in science against skepticism. It's also applied to concepts & mental content (as the intensions can be used as narrow content), metaphysics, and meta-philosophy. The range that Chalmers has on this is really incredible.
Chalmers comes out strong in his rigorous and lengthy defense and discussion of these theses. Moving from the PQTI basis to arguing for general scrutability theses with the Cosmoscope argument, and then arguing for A Priori Scrutability.
I do believe that Chalmers's strongest work in this book is Chapter 5: where he responds to Quine's Two Dogmas to defend the a priori. In this chapter, he develops a (primarily Bayesian) model of revisability and conceptual change. While not primarily focusing on Analyticity, it seems possible (if one is interested) that it could be extended to the defense of that as well.
Still, this project falls short. As other reviewers have noted, Chalmers fails to address the problems of diagonalization when adding (apparently whatever he wants) to the "compact" base. It also seems a bit ridiculous to suggest that one can add the entire totality of mathematical facts to the base if one has difficult problems with it. I'm unsure how compact 'compact' really is at this point... I didn't have strong issues with his section on minimizing the base and special cases, but the entire project at this point just seems to fall apart and is dubious.
Furthermore, the objection from applicability (i.e. how applicable these theses are to non-rational beings) still seems to have a strong weight, at least to me! I'm somewhat unconvinced by his response. And even if these are true, it seems unlikely that someone can actually solve the totality of facts, and construct those intentions, and so on... At which point, the project seems not very useful?
I guess, still, Chalmers puts out a very strong challenge from the Rationalists.
(p.s. It's also interesting to see the parallels into metaphysics in the 16th excurses: scrutability is a sort of epistemological supervenience).
The book is about a class of theses known as scrutability theses: the thesis that one can find all truths from a compact set of facts. If the scrutability thesis familiar, it is a project inspired by Carnap's Aufbau. As Chalmers puts it, his project can be seen as a form of Carnapian Rationalism.
Chalmers' main child is what he calls a priori scrutability. The thesis that from a compact set of facts, an agent can be in a position to know a priori that if C, then S, where Chalmers says that these compact set of facts is PQTI (the totality of physical and phenomenal facts with a That's All clause, and Indexicals). Carnap's Aufbau, on the other hand, used an entirely phenomenal and logical set of facts and attempted to use strict definitions rather than larger a priori relations.
Thus, Chalmers takes inspiration from Carnap's thesis, and does the following:
(1) Add much more to the base facts, and
(2) Weakens the relation that one can use.
The project is entirely epistemological, but Chalmers doesn't really attempt to be reductive in any other manner. He considers a large variety of these theses and defends a few of them. These theses become tools for Chalmers to construct and argue for the defense of other things. These theses first become tools that are used to define epistemically possible scenarios (by defining equivalence classes on the scrutable facts). Most notably to me, these scenarios are used to construct a kind of intension in a very Fregean manner. These intentions thereby help develop a kind of two-dimensional semantics (playing the role of the primary intension).
He also uses these defends structuralism in science against skepticism. It's also applied to concepts & mental content (as the intensions can be used as narrow content), metaphysics, and meta-philosophy. The range that Chalmers has on this is really incredible.
Chalmers comes out strong in his rigorous and lengthy defense and discussion of these theses. Moving from the PQTI basis to arguing for general scrutability theses with the Cosmoscope argument, and then arguing for A Priori Scrutability.
I do believe that Chalmers's strongest work in this book is Chapter 5: where he responds to Quine's Two Dogmas to defend the a priori. In this chapter, he develops a (primarily Bayesian) model of revisability and conceptual change. While not primarily focusing on Analyticity, it seems possible (if one is interested) that it could be extended to the defense of that as well.
Still, this project falls short. As other reviewers have noted, Chalmers fails to address the problems of diagonalization when adding (apparently whatever he wants) to the "compact" base. It also seems a bit ridiculous to suggest that one can add the entire totality of mathematical facts to the base if one has difficult problems with it. I'm unsure how compact 'compact' really is at this point... I didn't have strong issues with his section on minimizing the base and special cases, but the entire project at this point just seems to fall apart and is dubious.
Furthermore, the objection from applicability (i.e. how applicable these theses are to non-rational beings) still seems to have a strong weight, at least to me! I'm somewhat unconvinced by his response. And even if these are true, it seems unlikely that someone can actually solve the totality of facts, and construct those intentions, and so on... At which point, the project seems not very useful?
I guess, still, Chalmers puts out a very strong challenge from the Rationalists.
(p.s. It's also interesting to see the parallels into metaphysics in the 16th excurses: scrutability is a sort of epistemological supervenience).
August 3, 2016
Carnap was brilliant. So is Chalmers, who has improved upon Carnap's project. But I think we have another noble failure here. What's worse is that it is a quite long-winded failure. I can appreciate Chalmers' attempts at clarity and detail, but those aren't the only culprits for the longwindedness.
Excepting the prolixity, Chalmers does provide a fruitful examination of the plausibilities of various types of reduction. Further, perhaps the book's best contribution to philosophy is its defense of the a priori. Chalmers has opened the door more for a rationalist project. The superrigid tells us about everything beyond the scientific and phenomenal, says Chalmers. The a priori gets us all the rest of the truths.
But he tries to get us scrutability at the expense of metaphysics. I find the ontological, normative, and mathematical truths to push Chalmers' base beyond one we could call compact. Chalmers' hope to defend a scrutability base devoid of macrophysical truths is especially dubious. Categories such as truths of mathematics and set theory are exemplary of the basic problem of insufficient scrutability that I think Chalmers cannot overcome even with an enriched compact base. To parrot another reviewer, "You can't avoid the consequences of diagonalization by adding premises."
Excepting the prolixity, Chalmers does provide a fruitful examination of the plausibilities of various types of reduction. Further, perhaps the book's best contribution to philosophy is its defense of the a priori. Chalmers has opened the door more for a rationalist project. The superrigid tells us about everything beyond the scientific and phenomenal, says Chalmers. The a priori gets us all the rest of the truths.
But he tries to get us scrutability at the expense of metaphysics. I find the ontological, normative, and mathematical truths to push Chalmers' base beyond one we could call compact. Chalmers' hope to defend a scrutability base devoid of macrophysical truths is especially dubious. Categories such as truths of mathematics and set theory are exemplary of the basic problem of insufficient scrutability that I think Chalmers cannot overcome even with an enriched compact base. To parrot another reviewer, "You can't avoid the consequences of diagonalization by adding premises."
April 25, 2023
This is quite a wretched book. My wisdom in 'completing' it is questionable; alas, frustrations at the book led to various interesting discussions with Ben Goertzel, who nudged me to read it. Ben's comments on Constructing the World (CtW) tend to be far more interesting and insightful than the content of the book (unless you're very gifted in the art of generously reading interesting ideas between the lines). Charmingly, the author also recommends against reading much of the book.
The author very often claims that so-and-so topic is "dealt with in chapter such-and-such", yet when perusing the section, one finds the claim that its treatment will be "comically brief", i.e., underdelivering. This lack of integrity renders the book frustrating to read, as the author's claims as to the book's content cannot be trusted. A similar common issue is when the author notes that, perhaps, one will need to weaken the premises to push an argument through and then proceeds with the strengthed version. Such weakenings and the associated caveats can, in my opinion, obviously pile up.
As to the content, the vast majority seems to be responding to silly ideas of other analytic philosophers in "high school debate mode", as if all the author needs to do is to "refute all rejections" and then his claim that "X is possible" will stand strong, in a sort of anti-positivist style.
These features render CtW a knotted, noodly mess.
The core thesis is to defend the Laplace's Demon thought experiment: is it possible in theory for an ideally reasoning God-tier infinite mind to discern all truths from some relatively-compact class of base truths about the world without any recourse to experimentation?
I'd say there's a fairly standard commonsense idea that the laws of physics may indeed be such that one could in theory compute the unfolding from the big bang. Which is practically intractable, of course. Yet apparently attempts at actually specifying such formal systems and commonsense notions declaratively have failed -- and invited all sorts of weird counterexamples and issues to deal with. Bring on the debate ~ ~ ~
In simpler terms: is the world sensible or not?
Are there things that we fundamentally just can't get to the bottom of? -- Ok, we're limited beings, so let's talk about whether some infinitary perfect being could figure them out in principle!
My take is that Chalmers does not add much beyond inspiring people to think via overconfident confusion. Even where I don't necessarily disagree, I often remained unconvinced at the soundness of the reasoning in lengthy if-then rambling on some issue I care not much for.
The main cool takeaway is how he frames the "primitive classes" as PQTI (physical truths, phenomenal truths, a "that's all folks" truth, and indexical truths). The idea is that if you actually know that you have encapsulated all necessary truths about the world, then you can use negation by failure a la a closed-world assumption -- sort of equivalent to the theorem that you've solved everything. (Well, ok, the transfinite ideal reasoner can use negation by failure to determine all negative truths :'D.)
I'd probably frame this in terms of "Abstractions + Raw Experience" (to borrow friend Cosmic Zebra's terminology). Or we can be fancy and call it "Nomia" for mathematical laws. Or if setting laws aside, we'll have Mnemia (-- memory --) instead 😜.
... and, yet, where's the profundity in claiming that we can probably express all truths in terms of math and qualitative experiences? 🤷♂️
As far as I know, we are not sure how large the space of possible qualitative experience is -- and the space of mathematical truths is quite large.
I don't think the notion of "truth" is defined so clearly either and some of the "debates against other philosophers" seem to come down to quibbles as to what this actually entails.
"Frontloading" is basically the deduction theorem (outside the context of any particular formal system).
The comically brief treatment of hard cases is so laughably pathetic that it probably should have been omitted. E.g., non-determinism can be dealt with by keeping a history of what actually happens. Very deus ex machina. Math is dealt with by appealing to how we "just know" that "Peano arithmetic is true" in an a priori manner without need to recourse to proof of consistency. And how in infinitary minds, perhaps all mathematical truths can be ascertained or at least added to the compact base whose compactness is questionable (as other reviewers have noted). Yet in spite of this, the term "compact" is rampantly used throughout the text in spite of losing its integrity. This renders the work rather intellectually dishonest.
I hope to have more wisdom in approaching texts like this in the future 🙏🤓.
Anyway, if you are nonetheless intent on reading part of this book, I'd recommend like Chalmers to only read up to Chapter 2. Then skip everything and read the conclusion. Or just listen to the John Locke lectures (6 hours in total) that preceded the book. And please resist the temptation to see if "he actually deals with so-and-so in chapter bla". He probably doesn't in any sort of adequate manner.
On a positive note, the author seems to be shifting in a direction of superior writing (for lay audiences) and probing into "what is truth anyway?" with Reality+. To the extent that there are interesting ideas between the lines of CtW, I believe they should be explored in different manners. So may this tomb become history.
The author very often claims that so-and-so topic is "dealt with in chapter such-and-such", yet when perusing the section, one finds the claim that its treatment will be "comically brief", i.e., underdelivering. This lack of integrity renders the book frustrating to read, as the author's claims as to the book's content cannot be trusted. A similar common issue is when the author notes that, perhaps, one will need to weaken the premises to push an argument through and then proceeds with the strengthed version. Such weakenings and the associated caveats can, in my opinion, obviously pile up.
As to the content, the vast majority seems to be responding to silly ideas of other analytic philosophers in "high school debate mode", as if all the author needs to do is to "refute all rejections" and then his claim that "X is possible" will stand strong, in a sort of anti-positivist style.
These features render CtW a knotted, noodly mess.
The core thesis is to defend the Laplace's Demon thought experiment: is it possible in theory for an ideally reasoning God-tier infinite mind to discern all truths from some relatively-compact class of base truths about the world without any recourse to experimentation?
I'd say there's a fairly standard commonsense idea that the laws of physics may indeed be such that one could in theory compute the unfolding from the big bang. Which is practically intractable, of course. Yet apparently attempts at actually specifying such formal systems and commonsense notions declaratively have failed -- and invited all sorts of weird counterexamples and issues to deal with. Bring on the debate ~ ~ ~
In simpler terms: is the world sensible or not?
Are there things that we fundamentally just can't get to the bottom of? -- Ok, we're limited beings, so let's talk about whether some infinitary perfect being could figure them out in principle!
My take is that Chalmers does not add much beyond inspiring people to think via overconfident confusion. Even where I don't necessarily disagree, I often remained unconvinced at the soundness of the reasoning in lengthy if-then rambling on some issue I care not much for.
The main cool takeaway is how he frames the "primitive classes" as PQTI (physical truths, phenomenal truths, a "that's all folks" truth, and indexical truths). The idea is that if you actually know that you have encapsulated all necessary truths about the world, then you can use negation by failure a la a closed-world assumption -- sort of equivalent to the theorem that you've solved everything. (Well, ok, the transfinite ideal reasoner can use negation by failure to determine all negative truths :'D.)
I'd probably frame this in terms of "Abstractions + Raw Experience" (to borrow friend Cosmic Zebra's terminology). Or we can be fancy and call it "Nomia" for mathematical laws. Or if setting laws aside, we'll have Mnemia (-- memory --) instead 😜.
... and, yet, where's the profundity in claiming that we can probably express all truths in terms of math and qualitative experiences? 🤷♂️
As far as I know, we are not sure how large the space of possible qualitative experience is -- and the space of mathematical truths is quite large.
I don't think the notion of "truth" is defined so clearly either and some of the "debates against other philosophers" seem to come down to quibbles as to what this actually entails.
"Frontloading" is basically the deduction theorem (outside the context of any particular formal system).
The comically brief treatment of hard cases is so laughably pathetic that it probably should have been omitted. E.g., non-determinism can be dealt with by keeping a history of what actually happens. Very deus ex machina. Math is dealt with by appealing to how we "just know" that "Peano arithmetic is true" in an a priori manner without need to recourse to proof of consistency. And how in infinitary minds, perhaps all mathematical truths can be ascertained or at least added to the compact base whose compactness is questionable (as other reviewers have noted). Yet in spite of this, the term "compact" is rampantly used throughout the text in spite of losing its integrity. This renders the work rather intellectually dishonest.
I hope to have more wisdom in approaching texts like this in the future 🙏🤓.
Anyway, if you are nonetheless intent on reading part of this book, I'd recommend like Chalmers to only read up to Chapter 2. Then skip everything and read the conclusion. Or just listen to the John Locke lectures (6 hours in total) that preceded the book. And please resist the temptation to see if "he actually deals with so-and-so in chapter bla". He probably doesn't in any sort of adequate manner.
On a positive note, the author seems to be shifting in a direction of superior writing (for lay audiences) and probing into "what is truth anyway?" with Reality+. To the extent that there are interesting ideas between the lines of CtW, I believe they should be explored in different manners. So may this tomb become history.
January 29, 2019
heavy going, must try and read again.
November 28, 2016
His argument that experience itself is knowable (such as knowing what it is like to be a bat) is too large to assume.
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