Carnap’s quasi-analysis is usually considered as an ingenious but definitively flawed approach in epistemology and philosophy of science. In this paper it is argued that this assessment is mistaken. Quasi-analysis can be reconstructed as a representational theory of constitution of structures that has applications in many realms of epistemology and philosophy of science. First, existence and uniqueness theorems for quasi-analytical representations are proved. These theorems defuse the classical objections against the quasi-analytical approach launched forward by Goodman and others. Secondly, the (...) constitution of various kinds of structures is treated in detail: order structures, comparative similarity structures, mereological, mereotopological, and topological structures are considered. In particular, it is pointed out that there exist interesting relations between quasi-analysis and modern theories of pointless topology. (shrink)

We investigate the conditions under which quasianalysis, i.e., Carnap's method of abstraction in his Aufbau, yields adequate results. In particular, we state both necessary and sufficient conditions for the so-called faithfulness and fullness of quasianalysis, and analyze adequacy as the conjunction of faithfulness and fullness. It is shown that there is no method of (re-)constructing properties from similarity that delivers adequate results in all possible cases, if the same set of individuals is presupposed for properties and for similarity, and if (...) similarity is a relation of finite arity. The theory is applied to various examples, including Russell's construction of temporal instants and Carnap's constitution of the phenomenal counterparts to quality spheres. Our results explain why the former is adequate while the latter is bound to fail. (shrink)

In two occasions a Bibliography of Structuralism has been published in Erkenntnis (1989, 1994). Since then a lot of water has flowed under the bridge and the structuralist program has shown a continuous development. The aim of the present bibliography is to celebrate the 25th anniversary of the publication of An Architectonic for Science –structuralism’s main reference work– and of its recent translation into Spanish by updating the previous bibliographies with titles which have appeared since 1994 as well as before (...) that year but which are not included in them. As in the former deliveries, this bibliography only covers books and articles that are concerned directly with the structuralist approach in the philosophy of science. We would like to thank the many colleagues who have helped us in collecting all the information. Notwithstanding we apologize in advance for the possible entries that we missed to include in this third Bibliography of Structuralism. (shrink)

The concept of similarity has had a rather mixed reputation in philosophy and the sciences. On the one hand, philosophers such as Goodman and Quine emphasized the „logically repugnant“ and „insidious“ character of the concept of similarity that allegedly renders it inaccessible for a proper logical analysis. On the other hand, a philosopher such as Carnap assigned a central role to similarity in his constitutional theory. Moreover, the importance and perhaps even indispensibility of the concept of similarity for many empirical (...) sciences can hardly be denied. The aim of this paper is to show that Quine’s and Goodman’s harsh verdicts about this notion are mistaken. The concept of similarity is susceptible to a precise logico-mathematical analysis through which its place in the conceptual landscape of modern mathematical theories such as order theory, topology, and graph theory becomes visible. Thereby it can be shown that a quasi-analysis of a similarity structure S can be conceived of as a sheaf (etale space) over S. (shrink)