I am not familiar enough with Gödel's semantic completeness theorem. The explanation does not contain elaborate examples to illustrate the details of what they are talking about. It would be quite a job to inject examples in the right places. — alcontali

I am not familiar either, considering that I didn't understand its significance before yesterday. But from what I understand, it essentially states that inference and semantics are equivalent in a first order theory. If the theory knows something, it is true in all models (i.e. true for all interpretations consistent with the axioms), and if something is true in all models, the theory knows it. I don't find this surprising, as it makes intuitive sense. What I find more surprising is that it doesn't hold for higher order logics, as elaborated here:

The completeness theorem is a central property of first-order logic that does not hold for all logics. Second-order logic, for example, does not have a completeness theorem for its standard semantics (but does have the completeness property for Henkin semantics), and the set of logically-valid formulas in second-order logic is not recursively enumerable. The same is true of all higher-order logics. It is possible to produce sound deductive systems for higher-order logics, but no such system can be complete. — Wikipedia

A ring is "almost" a field -- it just lacks inverses (it is not closed under division) -- but that's the little I understand of why this ring is still a model (=σf-structure) of a field ... I hope that Wikipedia will manage to better elaborate on this subject. — alcontali

Actually, to my understanding, the signature is not a model, but the "embodied" part of the alphabet for the language of the theory - the rest being variables, quantifiers, logical symbols, are not specific or have no particular meaning. What the article states, if I read it correctly, is that the signature need not incorporate symbols, which taken as abstract mathematical objects, have semantics compatible with the models of the theory. This seems rather vacuous statement, considering that these are just symbols.

Edit: Thinking about it again, I probably overtrivialized the statement the article makes. It talks about the structure, not just the signature, which would include the interpretation and the domain as well. Considering their examples, you are right. And then indeed, it sounds a little non-sensical. But what they could mean is that an interpretation could assign 0 and 1 to their usual counterparts. And then addition, multiplication and inverses could map to relations that are subsets of Cartesian products of the integer set, but encode rationals using a pairing function. In other words, the article probably states that the function and relation symbols need not be mapped to their standard counterparts for the domain, but merely to functions and relations consistent with the theory.

I suspect that ZFC is not decidable, but then again, it really depends on the link between completeness and decidability. If there exists a procedure to solve the proof problem, the proof problem is decidable. That means that the theorem is provable from the theory. In that sense, provability is a decidability problem, because a proof is a procedure. — alcontali

I see. Thinking about it, semidecidability I imagine will carry a lot of practical utility for applications like automated theorem proving, even though it doesn't guarantee termination. Decidability is probably more crucial to theoretic analysis.

I think that it is the semantic completeness theorem that throws a spanner in the works: For a statement deemed true by the system, some proof must exist within the system. — alcontali

I actually don't know how the syntactic incompleteness was proven (through the same meta-logical argument as its semantic counterpart or not), but it seems that you shouldn't need a lot of semantics in order to demonstrate that some statement is independent. If the statement's derivation involves circularity (like the Gödel sentence), it should be entirely a deductive property if this circularity can be eliminated or not. But I might be wrong.

I am not intimately familiar with the subject, but I think there is some issue with the Wikipedia article.

There also may be linguistical confusion again. Many internet sources quote undecidability of PA, talking about sentences of PA's language that cannot be evaluated. The point is - sentences of the underlying language, not theorems of the theory, which implies that particular model semantics are involved. Otherwise, sentences that are not theorems (edit: themselves or their negations) don't have definite truth value in first-order theory, as per the completeness theorem. The wikipedia definition of decidability clearly talks about theorems only:

A theory (set of sentences closed under logical consequence) in a fixed logical system is decidable if there is an effective method for determining whether arbitrary formulas are included in the theory. — Wikipedia

Further in the decidability article, it is clearly stated:

Decidability should not be confused with completeness. For example, the theory of algebraically closed fields is decidable but incomplete, whereas the set of all true first-order statements about nonnegative integers in the language with + and × is complete but undecidable. — Wikipedia

Thus neither property implies the other. I should mention that I did confuse the issue somewhat, because recursive enumerability (i.e. effective axiomatization, semidecidability) is actually a weaker property, which does not answer negatively for statements not in the theory. Actual decidability requires negative and positive determination by effective method. Semidecidability is defined later in the same article. Even so, however, decidable, but incomplete theories, are also semidecidable, but incomplete ones. Thus, the statement holds that semidecidability does not imply completeness.

Edit: From reading on the web, I see that there is an important caveat. Every recursively enumerably axiomatizable theory is recursively enumerable. And every recursively enumerable syntactically complete theory is decidable. A complete theory may be undecidable, but for "sensible" theories (with effective axiomatization), completeness does imply decidability. So, as you stated, if ZFC were complete it would be decidable. But since it is not, does my original question - if it is decidable or not still stand? (That is, considering that it is effectively axiomatized, if that matters.)

Completeness. A set of axioms is (syntactically, or negation-) complete if, for any statement in the axioms' language, that statement or its negation is provable from the axioms (Smith 2007, p. 24). — alcontali

From the definition you quoted, a complete axiomatic theory has a proof for either the statement or its negation. That does not mean that all such proofs or statements can be enumerated by a single effective procedure simultaneously. (PS. According to the previous edit I made, the answer is yes, for the more conventionally axiomatized theories.)

The summary of Gödel's first incompleteness theorem in the introduction to the Wikipedia article (which you quoted) seems to talk about validity ("capable of proving all truths"), which is not trademark of the first theorem, but the second one. And the account differs from the formulation in the body of the article:

First Incompleteness Theorem: "Any consistent formal system F within which a certain amount of elementary arithmetic can be carried out is incomplete; i.e., there are statements of the language of F which can neither be proved nor disproved in F." (Raatikainen 2015) — Wikipedia

I reason, that for a statement to lack proof implies that it is not part of the axiomatization consequences. Not that it is part of the axiomatization consequences, but those cosequences cannot be computed.

Edit: Although, it appears that the theorem have been formulated for primitively recursively enumerable axiomatization originally. (According to this stackexchange remark.) According to the summary of one article I found, it appears to admit extension to non-enumerable theories.

And further in the article:

The first incompleteness theorem shows that the Gödel sentence GF of an appropriate formal theory F is unprovable in F. Because, when interpreted as a statement about arithmetic, this unprovability is exactly what the sentence (indirectly) asserts, the Gödel sentence is, in fact, true (Smoryński 1977 p. 825; also see Franzén 2005 pp. 28–33). For this reason, the sentence GF is often said to be "true but unprovable." (Raatikainen 2015). However, since the Gödel sentence cannot itself formally specify its intended interpretation, the truth of the sentence GF may only be arrived at via a meta-analysis from outside the system. — Wikipedia

This contradicts the summary, by clearly stating that validity is not the subject of the theorem. And finally, the following paragraph shows that the Gödel sentence is merely satisfiable in the standard model, not in every model:

Although the Gödel sentence of a consistent theory is true as a statement about the intended interpretation of arithmetic, the Gödel sentence will be false in some nonstandard models of arithmetic, as a consequence of Gödel's completeness theorem (Franzén 2005, p. 135). — Wikipedia

Talking about the relationship between syntactic completeness and decidability, I think that there is some definitional ambiguity again. I think that it is sometimes meant to imply a procedure for evaluating (assigning truth value) to all sentences of the language of the theory (which requires syntactic completeness), or procedure that enumerates all statements satisfiable by the standard model (which isn't actually semantic completeness, because all first-order theories are semantically complete, but completeness with respect to a model).

ZFC is subject to the diagonal lemma, and therefore is syntactically incomplete. Hence, it must necessarily have undecidable statements that can be expressed in first-order logic. — alcontali

My understanding from the definition was that for a theory to be decidable, it is necessary to have effective enumeration of its theorems, not to have a theorem for every statement or its negation. In that sense, I thought, whether ZFC is decidable is a separate subject matter from its syntactical incompleteness.

Concerning the implications of Gödel's semantic completeness theorem for other systems than Peano arithmetic, we are talking about advanced model theory, which is an enormous subject in itself. — alcontali

I understand, but just to clarify. I wasn't so much curious about Gödel's semantic completeness directly as application with respect to other axiomatic systems, i.e. examples of models that satisfy a statement that is independent of the axioms. I was wondering whether there exists a definition of some kind of "minimal" class of models for every theory. Because, as it stands, I am under the impression that semantic incompleteness says nothing that the syntactic incompleteness and semantic completeness theorems together don't say. If such models were defined and coincided with our "intuitive" definition of interpretation of a theory (similarly to what denotational semantics offers for recursive programs), and Gödel's semantic incompleteness were shown to apply to such models (i.e. they always satisfied a statement that cannot be derived from the axioms), it would make the claim stand on its own.

It is interesting to work on such explanation by examples, but then again, who else would be interested in reading the results? This discussion on the diagonal lemma is probably already more than what many potential readers would want to handle ... — alcontali

Absolutely. I will look into it on my own when I have the time. Logic is a past time interest for me, so I have gaps in my understanding at the moment. But I am trying to cure them, a piece at a time.

Thanks for the responses.

By the way, there is a problem with the terminology. Decidability is about computability:
...
While independence is about provability:
...
The difference between "undecidable" and "independent" seems to depend mostly "on the peculiarities of either formalism" rather than on truly fundamental issues. — alcontali

I think I understand the nuance. There are undecidable deductively complete theories, so claiming that an undecidable statement makes a theory deductively incomplete sounds strange. Saying that the statement is independent from the axioms, purely as a vocabulary, reduces the confusion.

I will also confess - I realized what profound misunderstanding of Gödel's semantic incompleteness I had. I believed that the theorem states that a valid (i.e. true in every model) statement can be independent from the axioms, which indeed would be exciting. Instead, it only states that a satisfiable statement can be independent. (Edit: And that such statement always exists for powerful enough theories.) The Gödel completeness theorem actually states the contrary to my prior understanding. That for first-order theories, validity and provability are the same. What a terrible confusion on my end. :)

Which makes me wonder. Since the semantic incompleteness proof holds for the standard model, what is the "intended" interpretation for other theories. Is there a criterion for a model being standard in general. For example, in denotational semantics of programming languages, a minimal interpretation is the least fixed point of a certain interpretation operator. I wonder, whether this has analogy for model theory. Such as, by using the compactness theorem and gradually building the interpretation domain, by arriving at domain entities using Skolemization or something.

I also couldn't clear up if ZFC is decidable, undecidable, or not yet established. Wikipedia indicates that there are only decidable sublanguages, while a stackexchange answer indicates that ZFC is recursively enumerable, which if mu-recursively enumerable, should mean that ZFC is decidable by Turing machines.

Given the Curry-Howard Correspondence, undecidability and independence overlap much stronger than suggested — alcontali

I find the Curry-Howard Correspondence a little strange. I'm sure it makes sense, but likening axioms to a pre-execution invariant and theorems to a post-execution invariant appears complicated. It may have something to do with formal verification processes, but for me, the relationship between proofs and computation appears to be about enumeration of proofs by turing machines in one direction, and the generation of booleans on the Turing tape for the proven theorems after every inference step in the other direction.

ZFC is not more powerful than PA because it knows more stuff. In fact, that would not be possible. Such theorem (as well as its proof) would still be a Gödel number which PA can also reach. Therefore, PA actually "knows" all possible theorems (and their proofs) that can be expressed in language. Therefore, it also knows all the axioms and all theorems (including their proofs) of all the other systems. The problem is that PA does not "trust" them. — alcontali

After clearing up my error in understanding, hopefully, I am not very surprised. Indeed, because of Gödel's completeness theorem, if a theory were able to prove a statement of PA that PA iteself couldn't, it would have fewer models. The stronger theory would not simply be deductively stronger, but semantically stronger. I was mistakenly excited that a theory with equivalent semantics (one that is expansion of PA) could cure PA's incompleteness. I was hoping that because the new axioms are not statements of PA itself, but their interpretations, they might result in some completely different configuration, without restricting the model space. But this is apparently not the case, at least for first-order logic.

Edit: correction about Gödel's completeness theorem - I used the term unsatisfiability, where I wanted to say not being valid or unsatisfiable (corrected now)

Thanks for the response. I'm sorry I couldn't respond earlier.

These "true but unprovable" statements will appear to use as simply undecidable. — alcontali

I couldn't express myself properly, but this is what I meant. I was attempting to construct an axiomatic system, whose undecidable sentences are not amenable to further evaluation by means of metalogic. The idea was to start with incomplete axiomatic system and to import proofs of undecidable statements by continuously adding meta-axioms. There were problems with this approach.

Number theory (by default: Dedekind-Peano) is a sub-theory of set theory (by default: ZFC), meaning that every number-theoretical theorem can be proven in set theory, but not the other way around. Now, there really are number-theoretical theorems that are fundamentally undecidable in number theory (=DP), but provable in the larger set theory (=ZFC): — alcontali

If I understand you correctly, there are axiomatic systems which preserve the truth values of all statements of Peano arithmetic, but make previously undecidable statements decidable? It is a curious fact. So, we don't actually have an axiomatic system yet, in which all statements of Peano arithmetic are decidable?

Now, we may not have fundamentally stronger theories than set theory (=ZFC). In other words, there may not be such larger theory of which set theory would just be a sub-theory. Therefore, when a theorem is undecidable in set theory, it may even be absolutely undecidable. — alcontali

Just thinking out loud, I wonder whether we would know if ZFC is semantically complete or not, if it were deductively incomplete? And what would be our course of action if we can't know? And on a related note, I wonder whether a theorem with the same quality as Chaitin's constant for Turing machines can be discovered for ZFC - having definite truth value, but no proof in logic or meta-logic.

One reason why we may not go higher nor further than ZFC, is because ZFC is already at the level of Turing-completeness -- can compute everything that is computable and therefore: can represent all knowledge that can be expressed in language. ZFC is possibly even stronger than that — alcontali

Yes, I think that it is also intuitive that ZFC cannot be weaker than a universal Turing machine. I also thought that it cannot be stronger. Since non-deterministic Turing machines are computationally equivalent to their deterministic counterpart and should be able to simulate successfully any deductive system. I mean - that was my intuition anyhow.

On the other hand, Turing Completeness is already a seriously constraining limit:

All known laws of physics have consequences that are computable by a series of approximations on a digital computer. A hypothesis called digital physics states that this is no accident because the universe itself is computable on a universal Turing machine. This would imply that no computer more powerful than a universal Turing machine can be built physically. — alcontali

I have wondered about this. I am not intimately familiar with the hypothesis, but it becomes ever more so obvious that material and abstract sciences are intertwined together. There are some implicit assumptions here, like discrete finite state and determinism. If I recall correctly non-determinism cannot produce more computability. But it can produce more outcomes, and I cannot tell whether this can contribute to nature somehow. Analog or infinite state may be unfeasible, as per QM. The hypothesis does depend on a number of assumptions, but may be true nonetheless.

Thanks again for the response. It is thought provoking.

I would like to rudely interject and ask a neophyte question that has been bugging me for some time. Tell me if you think it deserves a separate thread or has been previously addressed. I am not sure that it is worth its own thread and my understanding of the subject is somewhat limited.

Anyway, to my knowledge, the trick to Gödel's incompleteness is that it is about semantics. Originally the theorem was formulated in a syntactic variant, which was much more philosophically obvious, but was later refined to semantics, which is to me much more surprising. The theorem tells us that any sufficiently expressive axiomatic system is (ironically) insufficiently expressive to convey its own semantics.

Here is my question. Incompleteness is incurable - i.e. you cannot complete and incomplete axiomatic system by adding axioms. However, our very proof is done in formal logic, and thus provides a new axiomatic system, which embeds the previous one and eliminates the prior incompleteness by means of logical trichotomy - a statement of the original axiomatic system becomes either true, or false, or not provable (but semantically true or false). This new axiomatic system should be incomplete as well. But proving this would require embedding it once more, and reasoning in a similar way. Now, if we take the closure of this process - meaning, if we assume that any statement is provable if it is provable in at least one of the embeddings that define the semantics of the previous axiomatic system, then I speculate that we may be able to explore all embeddings in attempt to prove any statement using gradually expanding method, starting with finite inference steps in the basis axiom system and gradually adding inferences from the meta-systems. The point is - if we find no proof for a statement at all, than we cannot prove that it is semantically true, because it would mean that a proof existed in one of the embeddings, which is a contradiction. Therefore we cannot prove a statement that cannot be proven in this axiomatic system is semantically true, and to the extent of our logical method, this new axiomatic system can never be proven incomplete.

Or am I missing something here. Is there some uncountability involved or will the semantics eventually become inamenable to effective definition.

Edit: I think that I understand the problem now that I wrote it. :) I suspect that the semantics are not "continuous" with respect to the closure operation. The semantics of this new axiomatic system are probably not contained in the union of the embeddings. I can add the axiomatic system for the semantics of the closure to the list of axiomatic systems as well, but I suspect that this list cannot remain a sequence anymore, if I do this continuously.. and my proof method will probably fail.

Edit 2: To think about it - I am not sure whether an axiomatic system with proofs for all true statements of arithmetic exists. The semantic embedding, as I called it. Not for all statements true in its own semantics, just of arithmetic. Now I realize how many gaps I have in my knowledge. :)

To elaborate on the previous remarks, we don't see with our senses, but with our brains. Sensation is, for the most part, the act of altering the brain state in a manner that increases the mutual information that it shares with the external environment.

If by "figure out how reality actually looks like", you mean to make ourselves aware of the entire state of the universe (static and dynamic), I'm afraid this is not very likely. It assumes that an arbitrary human brain, or whatever other reasoning device we use in the future, would be able to hold all the information for such comprehension. If the universe is indeed quantum, as it currently seems to be, the only way in which I imagine this could happen is to merge ourselves in a singular intelligence that subsumes the entire universe, which is very futuristic.

If you mean to completely comprehend our immediate environment, by observing and reasoning about all processes happening on all smaller temporal and spacial scales directly around us, then this is slightly more likely. The problem is fundamentally the same - storage and processing capacity of our intellect, but if we augmented and offloaded some of it to devices in the "cloud", it is theoretically possible.

P.S.
I actually have to comment on something else. The universe has redundancy, which implies that the information content of its state may be stored in some strict subset of this state. Even if we assumed that this is technologically feasible, it complicates reasoning further, because in addition to prognosis, the intellect has to perform state inference to recover the redundancies that were previously compressed. Which implies a lot of concentrated processing power. If the state is not inferred, but directly perceived all the time, then the intellect is essentially merged with the universe, as previously mentioned, or at least unilaterally.

Einstein actually was amused by the opposite quality:
“The eternal mystery of the world is its comprehensibility…The fact that it is comprehensible is a miracle.”

There are many aspects of the universe that are overwhelming, but it is a compromise between nothing at all and anything whatsoever. In a sense, this volume of information is the middle ground. It is interesting that the state space of the universe might be exhaustible, because of its finite dimensions and quantum nature. This is curious constraint on the extent of our being.

Also, since levels of detail and degrees of separation act as a dampener of causality, there isn't always need to know every single detail. One possible speculation then is that the universe might work like an oracle machine - making up the answers as time progresses (assuming that time is not relational), but staying consistent. Currently, outside of QM on a very fine scale, there isn't any indication of this, that I am aware of.

Depends on what you mean by "know" and "exist".

For the first part, to me, knowing is acting modulo reasoning. For a pragmatic treatment (i.e. not spiritual one), reasoning is means to an end. It isn't there for your fulfillment. You know that you exist as much as you know that the stove is hot. In some sense, you don't. But acting like the stove is cold has consequences, and you choose knowledge as the opposite is not feasible. You are specific and in specific circumstances, and in no position to bail out from the present. You are already involved, and as a result you have to think in correspondence with the situation. Existence was there before you, and now you have to come to terms with it. The point - knowing about existence is like knowledge in general - a matter of necessity, prompted by the matter of fact.

As to what the concept of existence is. First, speaking generally, it is the quality of presence in the totality, or the rejection of the absence from the totality of things. In other words, it is a statement about the world. Your being posits that you are part of this totality and have agency in the universe. This is both vacuous and necessary. If you were not a part of the totality, then your reasoning wouldn't make sense. Thus, to think that you are not part of the totality is a contradiction. The key is - are you an absurdity? You either exist sensibly and think that you are, or you exist non-sensibly and think that you aren't (which will devolve and obstruct your agency in the world), or you don't exist, and you have no thoughts, or you don't exist and our logic is unsound, the universe is absurd, and your thoughts have no truth value. Which my reasoning (and probably yours) opposes instinctively, because it uses logic to operate. Which isn't a matter of choice.

A few caveats. There is also the question - how do you know that the world reveals the actual totality, and not a subset of it. You don't. Although, you act like you do by necessity.

Finally, from the point of view of spirituality, the above does not exhaust the question. But I don't think that there is anything spiritual that can be conveyed on that subject without some kind of specific meta-language and conceptualization of a different kind. Spirituality isn't a logical subject matter to begin with.

The question is about the definition (or arbitration) of merit or entitlement. But for a less ambitious treatment of the subject, I have to agree with the author that when people appreciate that they haven't earned something, especially a finite shared resource with recognized value, but extend grasp to acquire it, they are acting out of selfishness. Whether selfishness can be considered beneficial to society sometimes, like other forms of self-interest, is a separate pragmatic treatment of the subject matter. But as a personal quality, in peer interactions or self-assessment, I wouldn't commend selfishness (in the above sense), or aspire to it, if I can help it.

(People can be selfish out of their wits, instinctively. For example, in romantic affairs. I doubt that all selfishness can be repressed.)

I will abuse the thread just once more, because I didn't notice csalisbury remark on moral truths, which is also interesting. I wanted to state that I don't consider moral truths as truths in the same sense at all. They are rather akin to personal directives. They are however important for survival as well.

Having to be a responsible citizen is not "true". Society being adversely affected by irresponsible behavior is "true". Therefore, being a responsible citizen is an imperative to aid the group (whether the subject realizes it or not). Affections, morals, ambitions, all have this pragmatic dimension. They also carry self-expression, which is not less important for the individual. (That is, we have character, which is part of our reality as well, albeit on a personal level.)

Finally, conceptualizations, like cause and consequence, space and time, quantification, approximation, etc, are not truths, but methods of reasoning. They can be validated, but only in so far as they affect the decisions of the subject. They do not exist independently of the subject's interaction with the environment.

I think that some opinions stated here assume that acquisition of beliefs by the subject is through remote observation of consequences. That the facts do not affect the subject itself. But from my experience, the truth can and will (by all means) harm you, disable you, kill you if it can. You are forced to adapt or suffer, whether through your genetics, your cultural heritage, or your personal experience. You or your species will learn from adversity eventually (in a million years if necessary), or will part ways with nature. Truth earns meaning by enforcement, not gentle conviction. More than that - this compels it to consensus - sharing adversity.

I agree wholeheartedly with csalisbury, that for sentient beings seeking self-preservation (which is essentially given for sustained and independent sentient life form), the truth is both a relation between the personal view and the matter of fact, as required for correct decision making, and is also rejection of the penalty of living inefficiently and against the conditions of the environment.

Some caveats have to be addressed. There is difference between "the truth" and the quality of "being true". This is similar to the usage of "the world" and "worlds". To my understanding, we use "the truth" synonymously to the matter of fact. The latter doesn't need witnesses in order to be, at least in principle. For example, billions years ago, we were supposedly pieces of rock in the earth's crust. The precise details have no accounts by sentient species. The environment left traces, which we use to partially retrodict it, meaning that something was defined in detail, but the detail is not subject to experience. However "true" statements and ideas, or representations of reality used by intelligence of any kind (primitive or artificial one), can only qualify when there is a degree of purposeful behavior, determinism, interactivity, and pursuit. Otherwise, there is no meaning to calling the internal state of some system truth representative.

The second caveat is that without speculations regarding the universality, intransience, or at least statistical significance, the quality of truthfulness of statements and ideas can be very limited in scope. A person attached to reality simulator has to maintain correspondence and efficiency, but the limit to the representational and pragmatic aspects of their comprehension is set by the extent of the simulation. In a more realistic sense - a person's views are a product of time, culture, social class, etc. Their ideas and beliefs are reduced to this scope, somewhat ironically, by natural necessity. However, critical analysis of someone's personal belief in some extended scope, tentative as it might be, is justifiable as attempt at self-improvement. The concept of lasting, universal truth is similar to the projections of an architect for infinite maintenance and operation of the bridge they built, even though the bridge and the species that use it are likely to both have an expiration date.

There are two uses of the word in play. One is about what we take to be true. The other is akin to absolute truth. — frank

I think there is indeed some overuse of the term, which prompts me to blabber for a while here, to put my current thoughts on record if anything. Feel free to skip any or all of the following.

I think that you cannot say that a statement is true if it doesn't involve some interpretation. Also, many statements are not accounts of particular place at particular time, but principles. What makes them different is that they will be subject to interpretation contexts, some valid, some distorted. Meaning that an idea may be subject to the wrong interpretation. The interpretation has to be fixed first, to even talk about truth. Truth is not about the statement, but the belief in the fact matter of the statement, or the validity of the statement after "interpretation". (Note that in formal logic, the correctness of the interpretation is implied, but this is a foundational assumption that mathematics needs to make.)

If two people mean two different things by the same statement, those are not two different perspectives on the fact matter, those are two different vocabulary uses or mixed-up notions. We can achieve consensus about the proper (or "correct") interpretation of some notion or assertion, but this is not essential to the quality of truthfulness, but to the quality of communication. If on the other hand, two people actually mean the same thing by their statements, and they convey contrary statements (whose interpretations are directly contrasted), I believe that one of them is more true to the matter of fact.

To elaborate on the last point - what does it mean, and how does it become apparent, whether some view is true to the matter of fact. In my opinion, being true indicates that the subject has mentally captured some amorphous representation of its hosting reality, which affords it the benefit of making projected value judgements of its plans and actions. At least in the sense of the final utility of the interpretation of two opposed statements, one will carry more benefit then the other. Note that for interpretation that has no practical utility (such as a non-realizable belief), then its negation may have no direct application as well, but would be less costly, reducing the distortion of value and attention expenditure.

How does the utility of an idea become apparent - through adversity, failure, or demise. Or through expiration. If the utility of a non-factual idea works for one individual as a happenstance, or for groups of individuals as a transitory effect, it will probably become too costly for the majority eventually, as they contend between the resistance to change and their practical needs. The obsolete idea becomes expelled through exclusion.

Also, it is relevant that most statements are self referential. A statement about a statement requires interpretation whose subject matter are the interpretations of statements. For example, "this statement is true" can be seen as a statement, or as self-assertion. This nuance applies when we communicate - sometimes statements imply their truthfulness and are implicitly self-referential, and sometimes we elaborate them and don't comment on their truthfulness. But usually the outermost statements are implicitly self-asserting. Truth as a concept arises from this self-reference, by making statements about the interpretation of other statements.

English is not my native language, but I think what @alcontali provided in the first post as the U.K. definition is not accidental. To me, "mean" emphasizes that the person approaches his conflicts with cheap tactics and uses another person's unrelated disadvantages. For example, if a someone's parent dies and you remark that "you have both your parents" in attempt to humble them in a confrontation. (A child would say this sometimes.) Or if a person loses their child, loathing on it in justified anger, because said person was harmful to many, is still mean. Not because of the lack of compassion per se, but because their unfortune has beset them for reasons unrelated to their character, and the incident doesn't produce any morale. On the other hand, if their child dies as direct consequence of their own harmful actions, then a sense of gratification is not mean in my book. It may be wrong, or bad taste, but not mean.

To me, mean is a pejorative in the sense that someone is using their fortune or their opponent's unrelated misfortune when contending (verbally or otherwise) instead of opting for leveled play. This brings shame to the game, so to speak. It is social instinct to ostracize such behavior, whether it can be interpreted as rational or not.

I think you are avoiding the notion that all 'concepts' are denoted by 'words' which are socially acquired. — fresco

Words mediate concepts in our thought process, but they are not in themselves concepts. The interpretations of words require an interpreter and a universe, where the interpretation is "acted". The interpreter and context are not compelled into existence by language. If the interpreter acts irrationally by virtue of its conceptual understanding, it will face increased adversity. This decreases its odds for successful function (biological, social, etc). Even if very slowly, this will gradually eliminate or rectify the interpretation (by changing or destroying the interpretation bearer, its culture, its species, etc).

Convergent consensus may be inevitable, but only to the extent that human language users have large parts of their physiology in common. — fresco

They have a lot more in common, like culture, economy, ecological factors. Delusions are frequently part of the majority point of view. But they must still be acted out in ways that remain practical. Without practicality, a delusion will be self-destructive. As the technological and anthropological needs of a society increase, prior delusions lose practicality and are removed from majority consensus. New delusions appear in their stead, but reality does gradually settle in.

Now, it may be, that an 'uncommon physiology' like the brain of Einstein, can deconstruct previously 'useful' concepts like 'time', thereby triggering a paradigm shift with its associated 'concept/language revision'. — fresco

Einstein did not invent special/general relativity, just to break the mold. There were good and eminent physical reasons to do it (such as the relative consistency between the speed of electromagnetic waves and the rate of other physical phenomena in all reference frames), and there was already a vigorous debate concerning the meaning of time and space, before Einstein. Similarly, there were discussions about the wave and corpuscular nature of light prior to QM. There was of course conservatism, resistance to change, etc, but in both cases, empirical data prompted the developments in the conceptual model, not aesthetics.

I don't define it. It is a concept which denotes 'utility' of another concept and the utility of all concepts is relative to human needs. — fresco

I think of the relationship between reality and the personal momentary impression of utility like the direction of water molecules in the path of a water stream. Each molecule has a direction and is a quantity of water. However, it may or may not be consistent with the overall direction of the surrounding volume of water. And if it is inconsistent, it is likely that it will be altered, numerous times, with the overall tendency to follow the same path as the rest. Or not, but more likely, it will. The surrounding volume of water also may deviate from the total turn of the stream, due to an obstacle, for example. But ultimately, it will probably join with the rest. Or not, but usually it does. And if it does, by the time it does, the stream may have changed direction.

The point is, the water molecule can only account for its own motion. But there is such thing as consistency or inconsistency, and there is impact from the said consistency of motion that usually affects the individual molecule. Knowing this, one is tempted to talk about the shape of the stream bed, rather then the direction of that individual molecules, even if one is granted limited view of the body of water.

To claim that existence is relative is a restriction of scope - of single sentient point of view in a single instance of time. But it is not mandatory to commit to this scope for the purposes of methodological and epistemological analysis.

Some concepts imply expectance of lasting physicality and others do not. Concepts are denoted by 'words' whose abstract permanence suggests permanence of "objects' relative to human experience. — fresco

One could similarly argue that conceptualization is extrapolation of form derived from sensory experiences. You might then claim that you don't have concepts, but delusional elaboration of your senses. But if the concepts, sensory experiences, and the phenomena which cause them are joined in through methodical interactions, existence can be claimed in the usual way - through observational verification.

But concepts are all we've got ! — fresco

Concepts are like self-fulfilling prophecies. In the event of contention, each side assumes it is consistent with the human condition on a larger scale. Each side fights for recognition and self-affirmation, until the "correct" belief is justified if it becomes testable, and compels a wider consensus. Then, the relativistic conceptualization transcends its boundaries. Realism is a statement, that such convergence is inevitable.

How do you define existence?

If you define it relative to the individual experience, then it is relative to that one person. If you define it relative to the collective experience, then it is relative to that group. But if you define it relative to the total spatio-temporal configuration of the objects in the universe, then most people would call that absolute.

Now, I am not a physicist, but I do know that there are quite a few contending (equivalent, to the extent of their empirical confirmation) QM interpretations. Some allow you to make a claim that may never be verified - i.e. they are counterfactual.

I can tell you - this coin has "99%" chance to land tails, and if it lands heads, I can say that the result confirmed with my expectations. If I tell you (for the same coin) that it now changed and has "99%" chance to land heads, and it lands tails, I can take this as validation again. If the coin obeys consistent probabilistic behavior, the results will almost surely provide intuitive confirmation after infinite amount of time. But almost surely is not surely (and this is very important point). And infinite time is a lot of time. And no confidence can be extracted from observations performed without apriori model. (You need to have started with evolutionary trait that provides initial intuitions.) So, I am skeptical that we understand probability (other then according to our definitions), less so physical non-determinism. At this early stage, I think QM is a very nasty philosophical tool. We know how to use it and probability to our benefit, but that is far from complete understanding.

Regarding relativity, again, I'm not a physicist, but it seems to me that it offers a switch from the prior definitions, rather then a reform of our reality. Instead of measuring using a single device, or particular global periodic phenomenon, it measures relative to the local physical processes. Which, makes much more sense physically, but doesn't preclude any measurement of time or space one could wish. In fact, the theory doesn't really afford "ontological" space and time, merely parameters that trace the physical relations.

And non-religious people are also coping (and deluding themselves) by being unbelievers. Non-religious people are afraid of ever being held accountable, so their refusal to believe in a Creator is just the manifestation of their fear of responsibility. They just don't want to be responsible, and so they're afraid of judgement more than they're afraid of death. — Agustino

Self-judgement can be much harsher than the judgement of a benevolent creator. Most theists that I have known, seemed more relieved from their flawed human nature then I am.

@OP
I haven't read enough, but my personal pet theory has probably been regurgitated endlessly in the relevant literature. Here it is anyway.

Our intellect has historically emerged from filtration process that favors long term methodical behavior vs short term reactions. The reason is simple - chaos perseveres, but it forms nothing permanent to speak of, which means that it has no historical significance. Short term reactions are too inefficient for the long haul and don't produce sustainable presence. So, long term planning is necessary.

That is why, our mind is wired to search the space of possible outcomes, such that our reactions travel some path to a projected result that we desire. However, our long term goals are not always obtainable, or not even well defined. For unobtainable, you might want your loved ones to live with you forever, or to end all suffering around the world. For undefined, you might want to have a goal that surpasses all other goals, i.e. to achieve ultimate value without knowing what this value is.

Our mind is wired to experience gratification from the devising of a viable plan, and angst from the failure to do so. That is what compels a person into an intellectual frenzy to find means of attainment. But for some goals, such as those which are impossible, contradictory, or insufficiently specified, the mind becomes stuck in an operational deficit. To use an analogy, the planning behaves like a program taking all cpu time, preventing any other work from taking place, and preventing the termination of its own rampart operation.

When the inability to cope with a problem becomes evident on a subconscious level, yet the problem cannot be re-specified at the moment, the mind deliberately distorts the state space of projected outcomes (topologically or the valuation function) in order to relieve the subject. Without this defensive mechanic, thinking would cease immediately. In fact most problems statements are contradictory and unsolvable. For example - sustained health is impossible, because you are dying machinery since the day you were born. Personal participation (freedom) is limited, etc. The mechanism has planted roots in our culture, since most problems in life are hard. There are many extreme delusions, that are essentially necessary and have permeated the cultural mosaic of our societies.

I think that being happy without delusions is impossible, because your mind cannot cope with the realization that its priorities are impossible to satisfy and because your intellect is essentially self-conflicting. Happy or not, as long as you are exercising some semblance of thought process, your knowledge is partially repressed.

Out of curiosity, the classification above doesn't say, what one would be called if they disagree with the epistemic approach of believers, and not with the possibility (empirically unproven as it may be) of the existence of divine creator, capable of miracles or otherwise? Note that this is a strong methodological disagreement nonetheless. Would such people be "moderate" atheists, or "active" agnostics, since they are intolerant to (most) religious arguments. May be ignostics as another poster suggested.

Also, while theism might be defined as the belief in the existence of divine creator, this is not what religions are about. Most theists subscribe to some kind of ontology of the divine and the miracles it performs, various divine impersonations. An agnostic or an atheist might disagree to those no matter what their position on the issue of divine origin is otherwise.

Cool.
Regarding chiming in later, I am skeptical that I will make much progress, but I may look into semiotics (a good pointer by Wayfarer), and see what crystallizes out of it.

I will need some time to answer coherently, but I think that the difference between our points of view, about the significance of the subjective, is not one of essence, but one of purpose. I am looking to "understand" (which given the lack of data is a strong word) what a subject is, how it becomes a subject, what kinds of subjects, with what kind of qualities are potentially possible. You are looking into the application of the subject, what they can do better or worse, what is the way to improve their performance.

I am not looking into the discussion anthropocentrically. In a sense, I consider ignorance to be a disease, that experience (collective evolutionary as well as personal) cures with time. To understand the disease, I don't want to latch into the present condition of the existing species. I want to understand what drives the process, and arrogant as it may sound, where it means to converge. That is why I frequently make references to animal cognition, insanity, dementia, infant language-absent thought, etc, because those are the closest examples to the characteristic mental state of a human being, that are relatively well known, yet deviate enough to affect the capacity for rational thought.

Ok. Sorry if I overreacted or have been unintentionally inconsiderate myself.

Yes, I can see that. But thanks for your reply. — Wayfarer

That is fine. People cannot agree all the time.

On the other hand. Courtesy is its own argument. Becoming personal can discredit your statements.

Truth is a distinction, insofar as it is a member of a complementary pair, and if the capacity to make distinctions, that is, recognize a complementary pair, becomes lost, doesn’t that make the complement itself moot? If there is no making or comprehending a distinction, how can it be said there is one? — Mww

I am still thinking about it :) But I don't have the answers. Mutual information, correlation, isomorphism, etc, could help in defining mathematically a purely material concept of representation. Which I believe to be the objective component of the notion of fact awareness, which predicates understanding.

But from there on, how the subject emerges, and what additional faculties are necessary for them to experience and evaluate this fact awareness, I don't know. We know that belief is not the same as truth. (I am adamant that the mentally ill, very immature, very elderly, etc, should be part in any meaningful epistemic discussion.) Also, we know that understanding requires awareness, but not self-awareness. To define the relationship of truth and subject, we have to decide what a subject is. By which I mean - determine what kinds of subjects are there (or could be), and how does the type of subject affect the aforementioned relationship.

I don't want to examine my particulars. If I am going to talk about what a subject is, I would prefer a definition that doesn't rely on actual existence (, but rather just plausibility) of the subject, creating an epistemic reference context of some kind and a mapping to a material context.

Edit: In summary. I believe that the distinction between fact awareness and fact obliviousness can be defined objectively, as representation through material symmetry of some kind, whether with an implied emerging subject or not. The assignment of truth values is a different matter, which requires something more, which if materially expressed, is very hard to define.

I gave an argument, very early in this thread which is that there is no physical equivalent of the "=" sign. It can be extended to the argument that symbols, generally, which are the basis of language and abstract thought, can't be meaningfully reduced to physical laws (an observation which is the basis of the discipline of biosemiotics). — Wayfarer

The abstract notions, such as equivalence, causation, correspondence, etc, can be considered predicated by nature's reproducible conditions. For a naturalist, abstraction can be explained as emergence of generalizing faculties in the human cognitive apparatus, as optimal response to the exhaustible external varieties. If you imply that human sentience is irreducible to information processing, then you will not be satisfied with this answer.

Put another way, if the universe is, as materialism tells us, intrinsically meaningless, then how is meaning and reason grounded in it? — Wayfarer

The implied premise of the question, however, is that the search for (universal and eternal) meaning is not a rational need for foundational permanence. If it were, then it would make the universe meaningful by definition for a naturalist, because it is permanent, and a foundation onto itself. Such hypothesis may be overreaching, but so is the idea that the universe was conceived by an omnipotent creator, that is permanent and a foundation onto itself. The constructions are so similar, they end up being different on what seems like a technical note.

And, as remarked by one of Dennett's critics, 'if reason is a product of natural selection, then how much confidence can we have in a rational argument for natural selection ?' — Wayfarer

Human knowledge is fragile. You are correct, that any theory that supports that knowledge is corrigible attacks its own foundations. But given that human knowledge is indeed imperfect, shouldn't any sound epistemic theory have the obligation to model our understanding in such a way, as to seed reasonable doubt in its own validity, in consideration of its origin?

What it all comes down to, is that eliminative materialism doesn't succeed in eliminating the subjective reality of being; it basically ignores it, and then says 'what's the problem?' — Wayfarer

I don't understand how reducing the subjective states (mind) to objective states (matter) attacks the existence of the mind. This is the same as believing that allowing your doctor to examine your cough will destroy your cough from existence. I think it merely attacks the mind-body distinction. Allowing the mind to be understood empirically, does not disregard it. It rather appears to me, that dualism has a notion of the human soul, which is being attacked. But this is not the same thing as attacking the mind, except for a dualist. I dare say, I am an existentialist. I believe that if your values depend on your irreducibility, your ethical choices rest on the wrong premises. This explains why I don't subscribe to the objections against the "meaninglessness" of the material world onto itself.

Is 'eliminative materialism' an empirical hypothesis? Is there any conceivable way of determining whether it's true by empirical means? — Wayfarer

That is why I cannot argue that it is true. Only that it is self-consistent and plausible. Which you don't seem to agree to.
Edit: What methodology do you use to justify your disagreement with elminativism's self-consistency and plausibility, or is it a matter of incompatible premises of your philosophical position?
Edit 2: If you mean that empiricism cannot be validated externally by empiricism itself - this is true. But why do you think that it ought to be?
Edit 3: I just thought of another quality of eliminativism, as a hypothesis, that appeals to me. Minimalism. It assumes the least amount of unobservable externalities. I am assuming the moderate form of eliminativism the Oxford encyclopedia of philosophy refers to - that the mind is real, but is directly embodied.

But natural selection is a theory of the origin of species, and, as such, a biological theory. — Wayfarer

Whatever the originally intended scope was, natural selection can justify the emergence of social order and ethical standards in the social groups. In the article you referred me to, the author was arguing that the emergence of ethical standards is independent of the process of natural selection, wasn't he?

The dictionary should suffice. The definition of machines, devices, beings, and organisms, demonstrate that they are different in kind. — Wayfarer

You were arguing about the ontological content associated with different physical forms. You resolved this question by a dictionary lookup?

As far as science knows, this is only ever evident in the case that it forms the physical aspect of sentient beings. Took several billions of years, and stellar explosions, to happen, however ;-) — Wayfarer

We have developed the skill of engineering and have the resolve to embody the material expression of our intelligence into an artificially produced vessel. This will change the time scale significantly. For better or for worse, it has become essentially unavoidable at this point.

But then, for us, nothing is beyond the scope of biology, as we're material beings, and so ultimately explicable in scientific terms. — Wayfarer

The way I understand it, the real backbone of evolution is natural selection, not biology. Natural selection is determined by some biological traits, but it also involves all the particulars of the speciation process, including sociological or ecological factors. For example, the pollution of the ocean by plastic contaminants is not a biological phenomenon. However, it emerges as a product of collective behaviors that interact with the species' continuing adaptation and fitness.

Machines are devices, and devices are not beings. But again, you're explanatory framework may not permit the distinction. — Wayfarer

This is a very substantial postulate, that needs to have some rational grounds for me to accept it.

In other words, if you claim that empirical method is the arbiter in such issues, then you're basically want an empirical argument against empiricism. — Wayfarer

What is the alternative methodology? The least of what I want is to conclude at my premises, but I will not be convinced through sentiment either.

A property of what? Perceived by whom? — Wayfarer

As I said before, I am willing to allow that matter could be self-perceiving, under certain conditions. Our familiarity with matter is insufficient to make such judgement, but for me, it is a possibility. And I think that it requires the least amount of extraneous philosophical content. Considering the states of mind that an individual can experience, due to illness, or age, I can hypothesize a plethora of mental states. And since I am skeptical that our characteristic mental state is the only one that can sustain reason, I prefer to generalize philosophical arguments beyond the typical frame of mind.

You along with every physicalist/materialist worth his lab coat, property herein meaning something that belongs to a real substance. Not that you gave any indication you are one, just that experience informs me they think along the same lines you just spoke. — Mww

The less I try to postulate, the closer I become to the materialist view. Which is not to say, that I am against postulations that are undeniable by reason or nature. But the more I think about a statement, the more corrigible it seems. Hence, I drift towards materialism, as the most void philosophical position.

I rationalize the situation by coming at it from behind....I don’t have to prove subjectivity, but rather all I have to do is show how everything else becomes immediately unintelligible if there isn’t such a thing. — Mww

Depending on our definition, the subjective might be possible to stretch (in ways that actually interest me), and still maintain the capacity for reason.

I take that “something thinks, therefore something exists” and turn it into “I” am that which exists as thinking subject. “I” taken to represent the spontaneity of all thought in general, also called “ego” in empirical psychology, and the thinking subject taken to represent consciousness itself, which is the totality of conscious thought in general. — Mww

This certainly leans closer towards a definition of subject, that will resist attack, if awareness turned out to be potentially (or in some sense actually) impersonal.

Perhaps, but what good would a truth be if it wasn’t comprehended as such? — Mww

Tautologically, without the subject, the truth has no value to that subject. The necessity or capacity to make distinctions is lost to a non-extant subject, but does that preclude the truth from being in its own right? One could say, that we don't have to make such judgement, assuming the nature of truth does not impact our use of it. I am not sure of that.

Nahhhh.....I was just wondering if you held some unassailable truth. So as not to extend the concept of existence into the far reaches of dumb, an analytic proposition, which begins merely as something one thinks, would be true when its negation is impossible. The most famous one of all being cogito ergo sum. — Mww

Exactly my point. I would have said "necessitates the subject's existence", but the problem is - I am not sure that the subjective (in principle) is not an emergent, complex, partially distributed, potentially mutable property. I speculate that the subjective may depend on the relationship between constituents, as an expression of their organizational independence. Since I cannot be sure that the subjective is intrinsic indivisible immutable property, I cannot say "I think therefore I am", but rather "something thinks, therefore something is". For the latter, I can sort-of argue logically, using the necessity of logical models for the soundness of a statement, but still with many caveats.

I think the criteria for truth is the relation between subject and object, not always the existence of one or the other. The statement every effect has a cause is true, but neither cause nor effect exist. At least in the strictest sense. If we mean anything that is an object of thought exists just as objects of experience exist, such as concepts or ideas, then the answer to your question would have to be....both. — Mww

My point is - the subject (speaking now in a more narrow conventional sense) need not even comprehend the correlation as it applies, for it to be true. But if the subject doesn't comprehend the statement, what is their relation to the statement. One might say, that they still will experience the truth as an effect, but this bounds truth to experience. I am not sure this is the case, as it seems to me that truth may exist in its realization, without requiring knowledge. For example, simple mechanisms form a correct expression of some reality. An electronic thermoregulator can be "correct", in the sense that its internal representation of the environment state is amorphous to the actual state. The two states can be observed, their correlation or mutual information measured. In contrast, an "incorrect" thermoregulator would have states that exhibit less correlation, which is independent of the notion of its utility. So, in some primitive sense, one can talk about truth, even without awareness, just based on state correlations. There still has to be some state space for those correlating states, Thus even in this primitive case, you need some realization or existence. I am not arguing here whether correctness has value without a sentient subject. Neither whether reality without sentient subject can be ever validated, even if the truth would hypothetically still have proper mathematical definition.

A lot of modern thinking comes about because evolutionary biology occupies the place that was once occupied by religion. But whereas Western religion incorporated a sophisticated moral philosophy, derived from the Greeks as well as Biblical lore, evolutionary theory is really only a biological theory. So the attempt to shoehorn an explanation of all human nature into evolutionary theory is biological reductionism which is the default view of the secular-scientific culture. About which see this comment. — Wayfarer

I read the article, but I have to say, I disagree with a lot of it. I will present my critique.

I have no beef with entomology or evolution, but I refuse to admit that they teach me much about ethics. — Richard Polt

The evolutionary hypothesis does not mean to guide the population in its choice of ethics, It tries to support an explanation of how ethical choices are formed in a large statistical sample. What ethical choices should receive one person's privileged consideration is beyond its scope.

But since the human race has evolved to be capable of a wide range of both selfish and altruistic behavior, there is no reason to say that altruism is superior to selfishness in any biological sense. — Richard Polt

Considering only the biological level of the individual when interpreting natural selection is artificially limiting. There certainly are sustainable and unsustainable types of collective behaviors and group interactions. In that sense, choices are influenced by both biological and cultural speciation. I use the latter term in the sense that, for the purposes of natural selection, we don't inherit just our genes, we inherit our culture, our social context, even the state of the environment, which interact with the survival of the species in pretty much the same way. That is, selection of the fittest is capable of explaining what drove people to complex social order, cultural conservatism, and in the ethical plane (ontology of divine miracles set aside), religion as well.

In fact, the very idea of an “ought” is foreign to evolutionary theory. It makes no sense for a biologist to say that some particular animal should be more cooperative, much less to claim that an entire species ought to aim for some degree of altruism. — Richard Polt

Natural selection recognizes that cooperative (but competitive) member contributes to the thriving of its group. Species that act in pure chaos, driven only by self-interest, are not likely to persevere. Of course, evolution doesn't prescribe the range of ethical choices, but recognizes that choices that resolve poorly for the group won't have continuing place in history, as their presence will be eliminated through social ostracization or general extinction.

I prefer to conclude that ants are anything but human. — Richard Polt

The author frequently relates to some ant analogy, which apparently have been used to illustrate an evolutionary approach to social behaviors. Whoever used ants as an explanatory device, I am sure did not mean to assert that the human species are similar in their social dimension, but only that ants can be used to illustrate the formation of collective behavior or herd instinct from an evolutionary standpoint.

Whether we’re talking about ants, wolves, or naked mole rats, cooperative animal behavior is not human virtue. Any understanding of human good and evil has to deal with phenomena that biology ignores or tries to explain away — such as decency, self-respect, integrity, honor, loyalty or justice. — Richard Polt

Human beings are at the top of the evolutionary scale for a reason. The formation of social attitudes, of cultural norms, of instructional ideologies and religions produce more coherent group behavior (albeit not in every single instance). We all know that homo sapiens defeated (and ate) the neanderthals, because the latter, being averse or inept to the formation of large social groups, were forced to defend themselves in isolation. (To think of it, I am more of a neanderthal.)

Siri may find the nearest bar for you, but “she” neither approves nor disapproves of drinking. The word “bar” doesn’t actually mean anything to a computer: it’s a set of electrical impulses that represent nothing except to some human being who may interpret them. — Richard Polt

The author takes for granted that the structure of machines is incapable of sentience. This may or may not be true, but the author elaborates on the particulars of electrical circuitry, as if there is something inherently profane about them, which makes it unworthy of hosting sentient life. However, why electrical construction is fundamentally incompatible with life is not discussed.

None of these devices can think, because none of them can care; as far as we know there is no program, no matter how complicated, that can make the world matter to a machine. — Richard Polt

I am not aware of any accepted test that determines the presence of those attitudes in a non-human. And if the fact that we cannot test those qualities in machines with certainty is cause to withdraw speculations of machine sentience, then what tests have we used to confirm the universality of human sentience? Shouldn't the author present, in the context of his contrasting comparison, balanced empirical criterion for people and machines, and illustrate its failed application to machine behavior. Or otherwise, what criteria were used here - instinct?

Show me the computer that can feel the slightest twinge of pain or burst of pleasure; only then will I believe that our machines have started down the long road to thought. — Richard Polt

Again, essentially the same issue. The author is vague what type of demonstration would be sufficient. Admittedly machines today are still rather primitive, but in the hypothetical future when machines start to behave more elaborately, what test would satisfy the author or will he reject machine sentience purely definitionally? (On the other hand, machines may not be capable of sentience. But from my point of view, the author did not attempt to rationally prove this point.)

Without a brain or DNA, I couldn’t write an essay, drive my daughter to school or go to the movies with my wife. But that doesn’t mean that my genes and brain structure can explain why I choose to do these things — why I affirm them as meaningful and valuable. — Richard Polt

I wouldn't limit the causes of natural selection to genetics and biological structures. The factors are all encompassing - sociology, ecology and even cosmology can ultimately play a role. But even if ethical choices are explained by natural selection, that still does doesn't necessarily compel an individual to alter them. If my affection for my loved ones is explained, I wont erase them from my phonebook, just because my feelings have been reduced to primitives.

The author finishes by putting his views in historical context and then concludes that modern naturalism is an oversimplification of human life. Science indeed has the tendency to work in a narrow scope. It is abstract by design. But the author has not convinced me that science has chosen the wrong methodology to explain the emergence of ethical considerations, from an empirical standpoint. If the argument was non-empirical, then the essay should have established what logic would be used to validate it.

language, technology, science, arts, literature, philosophy.....what more evidence would you need? — Wayfarer

What I meant was, exceptionalism in its philosophical significance, which wasn't about a degree of accomplishment, which human beings obviously possess, but about fundamental differences between the species on which such accomplishment would have been predicated. That is - differences that cannot be explained in terms of gradual speciation, as Mww explained.

Just because we’re apex-intelligensia and apex-praedator in this environment through sheer evolutionary happenstance, says nothing about any other. — Mww

This seems to be an accurate interpretation of the known facts.

f you mean by “immutable comprehension” an irreducible understanding, is there no one simple thing for which you have no doubt at all? Or, is there no one simple thing for which the doubt of it contradicts something....or possibly everything.....else? — Mww

Are you hinting that truth implies existence? That any universal statement is implicitly about a model reality, and without reality, all universal statements are equivalent, making non-existence the mathematical definition of contradiction. Or am I misreading you. On a purely technical note - what about existential statements?

I am not able to articulate what I mean right now, but while I do believe to exist, there are qualities of existence that I question. Therefore it is difficult to analyze the relationships between existence and the particular states of being, such as reasoning, sensation (which I place in the same category as reason), rational truth, pragmatic truth, etc. Whose existence - the subject or the object - is a requirement for a statement to be true? Is truth a pragmatic or a rational quality - is the correct anticipation of your environment a sufficient operational equivalent to the ideal of truth? How does truth apply to different states of being - person with a damaged brain, baby, genius - does the notion apply to them in equal measure?

As I said, this line of reasoning is a little overwhelming and I fail to set it in order at the moment.

To be honest, I think that our opinions may be irreconcilable. I feel that the majority opinion is that humanity is entitled to some kind of exceptionalism, which I never understood. I admit that people may be exceptional, but I see no certain proof of it. My arguments are apparently, and probably justifiably (due to the flaws in them), not appealing enough.

I will however comment on this, because I thought it is interesting:

And finally, the epitome of logical reductionism is of course, the Aristotelian laws of thought, which makes explicit any theory defended by them does try to plant it right squarely into a sacred foundational principle. — Mww

I make my assertions corrigibly. I don't believe that I am capable of obtaining immutable principles. I possess modus operandi that is subject to continuous validation and refinement, and that is what make it a comprehension. Is logic corrigible? Could be. I rely on it, because I don't know any better and if I don't foster my conviction in some sensible image of reality, I will not be able to utilize my reason. But I doubt that immutable comprehension of any kind will be obtained by simple organisms such as ourselves anytime soon.

In any case, this was not a logical argument (obviously), just my point of view.

I would say we shouldn’t. Any sound philosophical position would seem to require either subscribing to a method which grounds it, or actually being a method in itself from which something else is grounded. — Mww

Every intellectual labor needs to commit itself to a manageable scope, that is true. But that does not imply, that the assumptions and methods therein are not consequently subject to further investigations or critical analysis. Furthermore, logical reductionism compels defensive thinking exactly for this reason - it tries to plant theories into sacred foundational assumptions, instead of investigating the logical interrelations between different kinds of statements. I prefer the later methodology, because it compels impartiality.

For example - despite appearances, I don't logically oppose dualism and idealism (even if I don't believe that all variants are sound), but I challenge the distinction between pantheism (consciousness as intrinsic matter potentiality) and eliminativism (matter in its own right), because I find that such distinction lacks reasonable explanation or definite value.

But from the context, it appears you are saying brain states that are not observable are hypothetical, and the epistemic substance of a hypothetical is questionable. — Mww

Observable, but not necessarily in the empirical sense. What I meant was that the notion should have a definite meaning and a clearly expressed value. Note that I don't consider it necessary for all notions to be of this variety, only those which are subject to critical thinking. But if they are not subject to critical thinking, how can they be subject of philosophy?

I would substitute logical for hypothetical, from which a valid method may follow necessarily, and there arises something on which to base our philosophical positions. — Mww

Being hypothetical is not an issue for me. My problem is lacking any kind of critical evaluation - logical (because of logical independence), empirical (because of disembodiment), experiential (because of indefiniteness). I am not opposing the idea that the mind can exist independently of reason - many things do. But if it is not planted in some kind of analytical framework, as you propose, then I cannot see how it can be a component of philosophy.

So, yes, I suppose it could be said I am indifferent towards the issue. I really don’t care about mind that much; it is enough that I exist as a thinking subject and if I happen to think about mind, I can only think so far and no further without venturing into the irrational. — Mww

You meant something more constrictive then I originally imagined. That your notion of the mind can be compared to a kind of bondage, similar to one's reaction to physical pain. Whatever its nature and substance might be, pain does provoke an adverse reaction in us, as this is its intended function.

Edit: I should be clear here. I don't oppose the mind as an instinctive notion, as long as it is treated skeptically in philosophical discussions. I don't oppose incorporating the mind as a philosophical hypothesis either, as long as it comes with some analytical content.

And to say from that, that the brain is observing itself, may be a conventional easement, it is nonetheless philosophically bankrupt, because it invokes a categorical error. Thinking is one thing, observing is quite another. — Mww

Actually, I was not trying to prove that sensation is recursive, but to weaken the argument that it couldn't be, because of unfoundedness. I wanted to make the argument, that if we assume that sensation cannot articulate its own structure, then we could make a similar argument that thinking about thinking or emoting about emotions is impossible. And the parallels I think hold well, because when I articulate my thoughts by thinking reflectively, the two thoughts are not incident, but the latter contains expressions of the former. I am able to investigate the nature of my thoughts, precisely because I am able to think about them, not merely to think in its own right. Similarly I would not be able to examine the nature of sadness, if I didn't feel any regret for it. But my regret for sadness, despite being a similar kind of emotion, is not coincidental with the sadness that provokes it. It is an expression of it. And our mental faculties are interwoven, such that we can think about our emotions, and emote on our thoughts. My argument is, that it would not be contrary to nature (i.e. paradoxical) if we could observe sensation through sensation. Our senses could express how our mental states work, just like the the rest of our mental faculties can self-reflect. Except that this self-reflection involves a space of greater complexity - the material world, which overwhelms our emotional and contemplative capacity.

In other words, treat beings as objects, no? — Wayfarer

Or treat objects as beings? Hence - pantheism and eliminativism seem the same to me..

While I might agree some brain states are experimentally quantifiable, insofar as reactive indicators are present for observation, I disagree that purely abstract mental conditions, that which is theorized as reason and its integrated particulars, will ever be displayed on a screen or graph. That is to say, the result of thought may be externally witnessed, but the machinations for its implementation, won’t. — Mww

Some hypothetical states might not be empirically verifiable, but the question is - are they epistemically substantive, and if not, why would we arbitrate our philosophical position for reasons that are not purely methodological? I mean, If we can't distinguish two positions in terms of their implications what is the difference between them? (Granted, there are positions that can be distinguished from materialism on that basis, such as the immortality of the soul, the existence of divine miracles, etc, but the notion of a mind existing separately, without further qualifications, does not appear to have immediate consequences in itself.)

I mean.....how does one even look for “understanding”? — Mww

For me, the question here is whether the mind is first and foremost a collection of unprocessed emotions and senses, aka the intentionality, or are we biased to prioritize these experiences, because they require less mental effort, whereas the more belaboring means of self reflection that involve logical inspection of the natural world, whilst much more intricate, taxing, and sometimes unreliable, can offer further detail of our state of mind, which we are not capable of perceiving directly through emotions.

Me, I just think it’s kinda funny, that physicalists/materialists in general tend to deny the philosophical paradigm, all the while employing the very thing for which the philosophical paradigm stands. — Mww

There is indeed a complication. Empirical observations as eliminativists would have them are recursive. For the brain to observe itself, it has to already be capable of sensation. But, I am not sure that this is contradiction. After all, the brain does not purport a different image - looking at your brain scan image does imply that your neurons are processing data about themselves. Also - the same recursion does exist backwards. A person can think or emote, or they can think or emote about the nature of their thoughts and emotions. While the latter actions involve greater sophistication, they are usually assumed to be fundamentally realized (whether metaphysically or biologically) in the same way as the former. The entire process could be described as such - through nature we can observe, us observing, us observing, or, observing others, observing us, etc.

Mind is merely a word, a placeholder for some immaterial totality, a sort of catch-all that for which we have no better word. If I reduce my thinking to a unconditioned necessity, I arrive at mind. — Mww

Still, don't you feel compelled to increase the comprehensiveness of your conceptualization? I mean, are you apathetic towards this particular type of knowledge as opposed to others, because you don't trust it is substantive? Or are you just indifferent towards the issue? I ask, because this is not how human curiosity generally operates. One could imagine what the world would be if Newton said - force is just a notion about a totality of interesting natural phenomenon and I don't have to investigate it any further.

On the other hand, I do acknowledge that we cannot validate claims in this area with certainty, probably because we don't even have a clear understanding of what the claims are. I sure don't.

Maybe not, but see the quagmire up ahead? — bongo fury

Not really. I am accepting of the idea, that the plants that I eat, or even the doorknob on my door, may possess some extremely small amounts of consciousness. I do not think a world with clear cut distinctions is necessary for people to function in it. But I did concede that such distinctions might exist nonetheless - because, while I do believe that the relationship between the quantitative and qualitative properties of matter has to be smooth (organization, being equal), it does not have to be gradual.