Many of the posts on this blog have advocated looking at rationality from the perspective that there is no meaning or semantics, only procedures and syntax. On reflection, it seems a very strange thing to suggest. There are some obvious intuitions that would totally reject such an idea. How on earth could there be no meaning?
Here are some of the obvious objections:
O1. Do you mean that "pear" does not necessarily mean pear and could equally mean apple? All verbal activity would be nonsense if such chaos reigned.
O2. "But I can *feel* the meaning of a word!"
O3. Can you do any logic without truth attribution? Truth attribution requires truth value. Where do truth attributions come from if not semantics?
O4. It is obvious that you have to go beyond words as strings of symbols in order to do science. The sentences themselves are true by virtue of the meaning that connects them to non-verbal knowledge, as in, for example, seeing something is true using vision.
Some qualifications will take care of the main thrust of O1 and O3. Semantics is understood to be a relationship between a word (or words) and the real world (or possible worlds). As opposed to that, there is syntax. Syntax is a formal system of manipulation, combination or substitution of symbols that operates without reference to the meaning of the symbols.
Semantics involves reference. The word "cats" refers to objects in the real world, namely cats. Oceans of ink have been spilled on the question of how this reference relationship is supposed to work; how it is justified, determined etc. The syntactic alternative is to say that, given a database of sentences, the symbol "cat" in one sentence accesses only the other sentences. (A simple example of what "accesses" means, pull out all the sentences in the database that contain the symbol "cat".) As opposed to the semantic notion of reference, the syntactic notion is very specific and can be made entirely explicit as long as an intrinsic rule for syntactic processing is accepted (see "Is Wittgen Justified?" for some discussion of intrinsic and explicit rules).
Some might argue that this kind of syntactic reference is just another kind of semantics. Using the term "semantics" in this sense is unobjectionable. However, there are two conditions that must be are kept to. Firstly, that reference is only to other sentences, strings of symbols or wff's participating in the same game or database. Secondly, that the reference relationship is purely formal, that there is an "effective procedure", or explicit rule, that evaluates that relationship. It is because semantic reference is usually intended to refer from the database of symbols to some reality "out there", that the words "meaning", "semantics" etc. have been rejected in favor of a wider use of the word "syntax".
O1 is not a problem because there are purely syntactic ways of preventing chaos. If I were to claim "John's roof is green", there is no need to resort to the semantic notion that a "roof" is a roof and not an apple. Assume that there are sentences with a high change cost, commitment level, beliefs or whatever, in my verbal system. These will be referred to here as "anchor sentences" instead of beliefs, in order to avoid talk of propositions and propositional states. Assume there are a set of anchor sentences such as "all roofs are red", "an object that is red is not green" etc. together with a set of explicit rules regarding words or word parts such as "all", "'s" etc. as well as rules about matching and contradictions. In that case, a purely syntactic formal process will conclude that either the anchor sentences get changed or the new sentence about John's roof gets changed/rejected. Thus chaos is averted.
Semantic theories are usually assumed to do the job of averting the chaos. However, Quine (1951) argued that the totality of sentences are required to justify a rejection and Putnam (1981) argues that even this totality is not sufficient for determining that "roof" does not actually refer to apples. Therefore it is syntax that averts the chaos and not semantics.
Anchor sentences are not necessarily true or even unchangeable. For a given verbal game, they are taken as sentences to be modified only as a last resort. Observation sentences tend to be anchor sentences. Core logical inference procedures tend to be anchor sentences; firstly, because it is psychologically very difficult to image an alternative state of affairs and also because they play an important part in all cognitive successes - from common sense to science and technology.
O3 refers to the fact that truth labeling is normally associated with any discussion of logic. Take for example a small axiomatic system that includes the axiom "A->(B->A)". This would be part of a syntactic formal system. However, one might find reference to the fact that truth tables can provide a semantic justification for the axiom. (Given the truth table for X->Y, the truth table for the axiom has all entries as true.) However, this truth-table effective procedure that gives this result, is not semantic in the sense objected to here, but is a purely formal system which therefore qualifies as a syntactic system. It is called semantic in this case firstly because it assigns truth values to both component and result and secondly because relative to the closed axiomatic system, it is a model or external domain.
A purely axiomatized logic does not actually care for any justification of its axioms, that is an external concern. However, one could say that the truth table formal system creates anchor formulae, here the axioms themselves for the logic.
O2 objects that meaning is an inseparable component of how we think about a word or sentence, assuming we understand it. This is not denied. However, this is just "what it is like" (to use Nagel's 1974 phrase) to understand a sentence. It is a fact about consciousness, that understanding-qualia have this nature. Consciousness is a complex subject in which, it seems, no progress has been made. However, the syntactic system of the brain does not require postulating any causal input from the conscious aspects of mind. Therefore, while there might be a feeling associated with a word, (perhaps it is a kind of observation of the process of the syntactic links between words and other words or words and images,) but it need not play any part in the analysis of the workings of rationality.
If meaning is to be understood only in this consciousness or qualia sense, then no objection is given to suggesting that it exists. However, in the process of defining it so, it should be removed from the current enterprise.
O4 objects that the verbal reasoning system cannot be the whole story. The verbal reasoning system refers either to the verbal component of an individual thinker or to an abstract reasoning system that is shared among multiple individuals. For the purposes the discussion now, only an individual is considered. The following discussion is therefore explicitly in the domain of philosophy of mind. It should not be confused with the general discussion of a syntactic verbal system, which is understood as general philosophy or epistemology.
Verbal reasoning is just one syntactic game. Verbal reasoning includes scientific, mathematical and logical symbols as well as the words of natural language. However it does not include pictures, images, audio etc. Verbal reasoning is a closed syntactic system except for the fact that it relies on external systems that anchor some of its statements. Thus "there is a table before me" or "the dial points to 3" is asserted to be an anchor by a visual, nonverbal subsystem. Two points can be made about the visual subsystem as opposed to the verbal subsystem. Firstly, it, too, is syntactic, but within a different game. Secondly, some parts of the visual system are accessible to conscious experiencing of its working.
The visual system is also a syntactic system. There are formal rules that translate, perhaps chaotically or non-deterministically, the images into anchor-sentences. They might use background knowledge and concepts, memory, Canny edges, stereoscopic registration and who knows what, but there is no reason to suspect anything but a formal process that works on databases of images, and association rules. Thus the visual system is syntactic too. Its symbols however include pixels, electrical potential, the states of color-responsive neurons, and, finally, words. One of the outputs of the visual subsystem is the assertion of a sentence. Thus, for the purposes of the discussion, (without intending to cut nature at its joints,) the visual subsystem includes an innate linguistic component that blurts out, as it were, "I see a table".
The second point to be made about the visual subsystem, which applies to other subsystems of the mind, is that consciousness observes or experiences its workings too. There was never any intention to identify the verbal reasoning system with the conscious mind and to assert that the anchoring process for some verbal assertions is non-conscious or innate. Thus we both experience certainty about sentences such as "there is a table before me" as well as experiencing the source of that certainty, namely, the visual experience. The claim is that reasoning is limited to the verbal subsystem, but not that it is all that we are.
Nevertheless, only the verbal game is reasoning. It is not the only contributor to knowledge, but the verbal subsystem is what reasoning is.
References:
Nagel, T. (1974). “What is it like to be a bat?” Philosophical Review, 83: 435–450.
Putnam, H., 1981, Reason, Truth and History, Cambridge: Cambridge University Press.
Quine, W. V., 1951, ‘Two Dogmas of Empiricism’, Philosophical Review, 60:20-43
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