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The logic of empirical theories
‘94
Studies in History and Philosophy of Science
discussion is full of interesting insights. As it stands, I fear it leaves too much implicit, placing a far too heavy burden on the reader. I can see where Yolton’s book will be of lasting use to the student, as a companion to the Essay, and to the scholar pursuing certain lines of research. One of its strongest points derives from Yolton’s historical awareness, not treating Locke as an isolated phenomenon in the history of philosophy, but as having some real connection with the intellectual activity going on around him. There is a lot of good material in this book. It is unfortunate that it does not hang together in a more distinctive way. MARGARET J. OSLER Harvey Mudd College, Claremont
Marian Przelecki, The Logic of Empirical Theories. London: Paul, 1969. v+ 108 pp. &x.87.
Routledge
& Kegan
Przelecki’s monograph is devoted to a limited set of problems in ‘the logic of empirical theories’, and approaches them in a very specific fashion. The major problems are, generally, the interpretation of empirical theories, and the distinction between empirical and a priori elements in them, together with, more specifically, the explication of the notions of meaning postulate, analyticity, empirical meaningfulness for sentences and so on. The basis of the analysis is the semantical theory of models and the stipulation is that by ‘empirical theory’ is intended ‘formalized empirical theory’. The elaboration of the basic application of the model-theoretic view in this field is fairly clear but suffers somewhat from the brevity to which it is constrained. It is irritating that the bibliography is so short and it would have been very helpful had there been citations given for further reading on the specific important conclusions mentioned in the text. Przelecki’s aim of making the monograph self-contained has the unfortunate consequence of minimizing its effective open-endedness. Formalistically inclined writers not infrequently exaggerate the clarity and intuitiveness of the primitive terms on which they build their logical structures and Przelecki follows suit. The basic notion of model for a language is introduced as ‘intuitively speaking, any fragment of reality about which this language can speak’. Confident that ‘this intuitive content is exceedingly simple and clear’, Przelecki proceeds to give explications of other concepts such as truth, falsity, determinateness, and so on. Primarily concerned with the interpretation of formalized theoretical languages, he gives a relatively prolonged account of a variety of different types of meaning postulates designed to introduce clear-cut theoretical predicates and dispositional terms into scientific discourse. It is interesting to contemplate in the case of a brief text of this kind which, though admitting that it does have controversial presuppositions, cannot afford space to examine them, how best to reconstruct those basic commitments. For
Reviews
‘95
example, we may note that the model-theoretic approach to the interpretation of a theoretical language, L,, is based on the notion of a prolongation of the model of the pure observation language, Lo. This is essentially the inclusion of a further set of predicates into the model of Lo, and in no way appears to involve an extension of the universe of discourse. Przelecki devotes some considerable amount of space (considering the brevity of the text) to pointing out, even with the aid of formal arguments, the important commonplace that non-linguistic, ostensive ‘definition’ is necessary for terms in Lo. This ostensive definition, in Przelecki’s own words ‘an efficacious mental training rather than a cogent logical operation’, introduces the scientist to the universe of discourse of the model and the subsets of it which are each denoted by observational predicates. This universe must then serve as the universe of discourse of the model of every theoretical language which has as its model a prolongation of that of Lo. It strikes this reviewer as an absurdly powerful restriction to place on the introduction of scientific theories, albeit highly idealized ones. Thus assuming a realist position on the existence of electrons, we should have to include in the universe of discourse of Lo a host of uncomfortably non-observational entities as preparatory to the introduction of, say, electron theory’s model as a prolongation of that of our observation language. Przelecki’s sensitivity to the fact that a pure observation language is at least an implausibility is reflected in his adopting the suggestion that a theory such as chemistry be ‘introduced’ on the basis of physical theory. He recognizes that theories are, in general, only introduced into a theoretical context. Thus the preferred models of chemistry should be prolongations of that of physics (subject to the requirement of the truth of a privileged set of meaning postulates in all of them). Przelecki extends this idea of a multiple succession of prolongations to explain his intuition that ‘no scientific language contains a part that might be identified with . . . Lo’, the pure observation language. Indeed, ‘every term in science is governed by some meaning postulates’. Unfortunately, Przelecki’s use of the notion ofprolongation does not allow him totally to eliminate Lo as the basis of his attempt to solve this problem by dividing theoretical discourse into a basic part and the rest. The basic part, although already a genuine theoretical language, plays the role originally played by Lo, but all its terms now are governed by meaning postulates. Aware that Lo has still to be used as the basis of both parts of the theoretical language (on pain of complete vagueness of the theoretical terms), Przelecki appeals to the reader to countenance Lo as, possibly, ‘a part of pre-scientific, everyday discourse’. In the face of our prescientific, everyday knowledge of such discourse, it seems implausible to equate it to Lo in the ‘strict meaning’ given the latter. Even less plausible is Przelecki’s alternative suggestion of considering Lo as ‘a useful epistemological fiction’. We should rather than anything else, emphasize the ‘fiction’, for the avoidance of indefinite vagueness in the denotation of terms for a language user is dependent on his or her actual use of ostensive definition and certainly not on the jictional use of it. JOHN M. NICHOLAS University of Western Ontario
Studies in History and Philosophy of Science
discussion is full of interesting insights. As it stands, I fear it leaves too much implicit, placing a far too heavy burden on the reader. I can see where Yolton’s book will be of lasting use to the student, as a companion to the Essay, and to the scholar pursuing certain lines of research. One of its strongest points derives from Yolton’s historical awareness, not treating Locke as an isolated phenomenon in the history of philosophy, but as having some real connection with the intellectual activity going on around him. There is a lot of good material in this book. It is unfortunate that it does not hang together in a more distinctive way. MARGARET J. OSLER Harvey Mudd College, Claremont
Marian Przelecki, The Logic of Empirical Theories. London: Paul, 1969. v+ 108 pp. &x.87.
Routledge
& Kegan
Przelecki’s monograph is devoted to a limited set of problems in ‘the logic of empirical theories’, and approaches them in a very specific fashion. The major problems are, generally, the interpretation of empirical theories, and the distinction between empirical and a priori elements in them, together with, more specifically, the explication of the notions of meaning postulate, analyticity, empirical meaningfulness for sentences and so on. The basis of the analysis is the semantical theory of models and the stipulation is that by ‘empirical theory’ is intended ‘formalized empirical theory’. The elaboration of the basic application of the model-theoretic view in this field is fairly clear but suffers somewhat from the brevity to which it is constrained. It is irritating that the bibliography is so short and it would have been very helpful had there been citations given for further reading on the specific important conclusions mentioned in the text. Przelecki’s aim of making the monograph self-contained has the unfortunate consequence of minimizing its effective open-endedness. Formalistically inclined writers not infrequently exaggerate the clarity and intuitiveness of the primitive terms on which they build their logical structures and Przelecki follows suit. The basic notion of model for a language is introduced as ‘intuitively speaking, any fragment of reality about which this language can speak’. Confident that ‘this intuitive content is exceedingly simple and clear’, Przelecki proceeds to give explications of other concepts such as truth, falsity, determinateness, and so on. Primarily concerned with the interpretation of formalized theoretical languages, he gives a relatively prolonged account of a variety of different types of meaning postulates designed to introduce clear-cut theoretical predicates and dispositional terms into scientific discourse. It is interesting to contemplate in the case of a brief text of this kind which, though admitting that it does have controversial presuppositions, cannot afford space to examine them, how best to reconstruct those basic commitments. For
Reviews
‘95
example, we may note that the model-theoretic approach to the interpretation of a theoretical language, L,, is based on the notion of a prolongation of the model of the pure observation language, Lo. This is essentially the inclusion of a further set of predicates into the model of Lo, and in no way appears to involve an extension of the universe of discourse. Przelecki devotes some considerable amount of space (considering the brevity of the text) to pointing out, even with the aid of formal arguments, the important commonplace that non-linguistic, ostensive ‘definition’ is necessary for terms in Lo. This ostensive definition, in Przelecki’s own words ‘an efficacious mental training rather than a cogent logical operation’, introduces the scientist to the universe of discourse of the model and the subsets of it which are each denoted by observational predicates. This universe must then serve as the universe of discourse of the model of every theoretical language which has as its model a prolongation of that of Lo. It strikes this reviewer as an absurdly powerful restriction to place on the introduction of scientific theories, albeit highly idealized ones. Thus assuming a realist position on the existence of electrons, we should have to include in the universe of discourse of Lo a host of uncomfortably non-observational entities as preparatory to the introduction of, say, electron theory’s model as a prolongation of that of our observation language. Przelecki’s sensitivity to the fact that a pure observation language is at least an implausibility is reflected in his adopting the suggestion that a theory such as chemistry be ‘introduced’ on the basis of physical theory. He recognizes that theories are, in general, only introduced into a theoretical context. Thus the preferred models of chemistry should be prolongations of that of physics (subject to the requirement of the truth of a privileged set of meaning postulates in all of them). Przelecki extends this idea of a multiple succession of prolongations to explain his intuition that ‘no scientific language contains a part that might be identified with . . . Lo’, the pure observation language. Indeed, ‘every term in science is governed by some meaning postulates’. Unfortunately, Przelecki’s use of the notion ofprolongation does not allow him totally to eliminate Lo as the basis of his attempt to solve this problem by dividing theoretical discourse into a basic part and the rest. The basic part, although already a genuine theoretical language, plays the role originally played by Lo, but all its terms now are governed by meaning postulates. Aware that Lo has still to be used as the basis of both parts of the theoretical language (on pain of complete vagueness of the theoretical terms), Przelecki appeals to the reader to countenance Lo as, possibly, ‘a part of pre-scientific, everyday discourse’. In the face of our prescientific, everyday knowledge of such discourse, it seems implausible to equate it to Lo in the ‘strict meaning’ given the latter. Even less plausible is Przelecki’s alternative suggestion of considering Lo as ‘a useful epistemological fiction’. We should rather than anything else, emphasize the ‘fiction’, for the avoidance of indefinite vagueness in the denotation of terms for a language user is dependent on his or her actual use of ostensive definition and certainly not on the jictional use of it. JOHN M. NICHOLAS University of Western Ontario