Contemporary pragmatists individuate theories semantically.
Two theory expressions are different theories either if the expressions have different test designs so they identify different subjects, or if the expressions make contrary claims about the same subject as defined by the same test design.
Criticism:
Contemporary pragmatists recognize the empirical criterion as the only valid decision criterion that yields scientific progress.
On the pragmatist thesis of ontological relativity, semantics and ontologies can never trump the empirical criterion for criticism. Acceptance of ontologies is based upon empirical adequacy of a theory as demonstrated by empirical test outcomes. Thus contrary to romantics, pragmatists permit description of subjective mental states in social-science theories and explanations, but never require such description as a criterion for criticism. Or as Popper said, science is “subjectless”.
Pragmatists recognize the nontruth-functional hypothetical-conditional form of statement-schema for expressing proposed theories.
Pragmatists recognize the modus tollens falsifying argument for empirical testing of the theories.
Unlike the logical positivists, pragmatists do not recognize the Russellian truth-functional conditional logic for scientific criticism, because the logic of empirical testing is not truth-functional.
Explanation:
Explanation describes the occurrence of individual events and conditions as caused by the occurrence of other described events and conditions according to law statements.
Pragmatists recognize modus ponens nontruth-functional deductive logical argument with the hypothetical conditional statement form that includes universally quantified statements expressible in conditional form that are scientific laws. Whenever possible the explanation is predictive.
Laws are said to be “explained” in the sense that a set of logically related laws may form a deductive system partitioned into dichotomous subsets of explaining antecedent axioms and explained consequent theorems.
Chapter 3. Philosophy of Language
Many and probably most of the central concepts and issues in philosophy of science involve philosophy of language. Therefore the following selected elements of contemporary pragmatist philosophy of language are discussed in relation to philosophy of science.
3.01 Synchronic and Diachronic Analysis
To borrow some terminology from Ferdinand de Saussure’s classic Course in General Linguistics language analyses may be either synchronic or diachronic:
The synchronic view is static, because it exhibits the state of a language at a point in time like a photograph. And to borrow some terminology from Rudolf Carnap’s Meaning and Necessity with a revised meaning, in computational philosophy of science the state of the language for a specific scientific problem is displayed synchronically in a “semantical state description”. In the pragmatist’s semantical state description statements both of theory language and of the law language in the relevant test design function as semantical rules that describe the meanings of their constituent descriptive terms.
The diachronic view on the other hand exhibits two chronologically successive states of the language for the same problem as defined by a test design, and shows semantical change over the interim period. Then the view is a comparative-static semantical analysis like “before” and “after” photographs. And if a transitional process between the two successive language states is also described, as in the computer code for a discovery system, then the diachronic view is dynamic like a motion picture.
3.02 Object Language and Metalanguage
Many philosophers of science such as Rudolf Carnap in his Logical Syntax of Language distinguish two levels of language, object language and metalanguage.
Object language is used to describe the nonlinguistic real world.
Metalanguage is used to describe language, either object language or metalanguage.
The language of science is typically expressed in the object-language perspective, while much of the discourse in philosophy of science is in the metalinguistic perspective. Terms such as “theory” and “explanation” are examples of expressions in metalanguage.
3.03 Dimensions of Language
The metalinguistic perspective includes what may be called dimensions of language, which serve well as an organizing framework for philosophy of language. Four dimensions may be distinguished for philosophy of language. They are A. syntax, B. semantics, C. ontology and D. pragmatics. Most philosophers of science ignore the linguists’ phonetic and phonemic dimensions. And most linguists ignore ontology.
A. SYNTAX
3.04 Syntactical Dimension
Syntax is the system of linguistic symbols considered in abstraction from their associated meanings.
Syntax is the most obvious part of language. It is residual after abstraction from pragmatics, ontology, and semantics. And it consists only of the forms of expressions, so it is often said to be “formal”. Since meanings are excluded from the syntactical dimension, the expressions are also said to be semantically “uninterpreted”. And since the language of science is usually written, the syntax of interest consists of visible marks on paper or more recently linguistic displays on computer display screens the syntax of expressions is sometimes called “inscriptions”. Examples of syntax include the sentence structures of colloquial discourse, the formulas of pure or formal mathematics, and computer source codes such as FORTRAN or LISP.
3.05 Syntactical Rules
Syntax is a system of symbols. Therefore in addition to the syntactical symbols and structures, there are also rules for the system called “syntactical rules”. These rules are of two types: formation rules and transformation rules.
Formation rules are procedures described in metalanguage that regulate the construction of grammatical expressions out of more elementary symbols.
Formation rules order such syntactical elements as mathematical variables and operator signs, descriptive and syncategorematic terms, and the user-defined variable names and reserved words of computer source codes. Expressions constructed from the symbols in compliance with the formation rules for a language are called “grammatical” or “well formed formulas”, and include the computer instructions called “compiler-acceptable” and “interpreter-acceptable” source code.
When there exists an explicit and adequate set of syntactical formation rules, it is possible to develop a type of computer program called a “mechanized generative grammar”. A generative grammar constructs grammatical expressions from inputs consisting of more elementary syntactical symbols. The generative-grammar computer programs input, process, and output object language, while the source-code instructions constituting the computer system are therefore metalinguistic expressions.
A mechanized generative grammar is a computer system that applies formation rules to more elementary syntactical symbols inputted to the system, and thereby outputs grammatically well formed expressions.
When a mechanized generative grammar is used to produce new scientific theories in the object language of a science, the computer system is called a “discovery system”. Typically the system also contains an empirical test criterion for the selection of a subset for output of the numerous theories generated.
A discovery system is a mechanized generative grammar that constructs and may also empirically test scientific theories as its output.
Transformation rules