2 Popper's Logical Definition of Verisimilitude. 3 Popper's Probabilistic Definition of Verisimilitude. 4 Conclusion.

Of two false theories, One can be, Intuitively, Closer to the truth than the other. The purpose of the article is to propose a rigorous explication of this intuitive notion.

It is well known that the manner in which a definitely descriptive term contributes to the meaning of a sentence depends on the place the term occupies in the sentence. A distinction is accordingly drawn between ordinary contexts and contexts variously termed non-referential, intensional, oblique, or opaque. The aim of the present article is to offer a general account of the phenomenon, based on transparent intensional logic. It turns out that on this approach there is no need to say (as (...) Frege does) that descriptive terms are referentially ambiguous or to deny (as Russell does) that descriptive terms represent self-contained units of meaning. There is also no need to tolerate (as Montague does) exceptions to the Principle of Functionality. The notion of an ordinary (i.e., non-intensional) context is explicated exclusively in terms of logical structure and it is argued that two aspects of ordinariness (termed hospitality and exposure) must be distinguished. (shrink)

Chapter One: Constructions. Entities, constructions, and functions When one travels from Los Angeles to New York, going, say, by way of St. Louis, Chicago, ...

Intensions feature prominently among the entities we talk about.

Pár slov úvodem k dopisu, který poslal Pavel Tichý z University of Otago Pavlu Maternovi (který v té době ´pracoval´ na brněnské univerzitě bez možnosti učení a publikování). K dataci dopisu: Shoduji se s odhadem Dr. Raclavského, že jde patrně o r. 1975. Ti, kdo neprožili normalizaci, si těžko představí situaci. To nebylo tak, že můj přítel Tichý momentálně působí na Novém Zélandě a píše mi z momentálního zahraničního pobytu. Tichý byl emigrant, což mj. znamenalo, že žádnou z jeho (...) odborných statí nebylo možno u nás citovat, dále že dík faktu, o kterém každý věděl, že dopisy emigrantů jsou u nás na příslušných institucích otvírány, znamenala korespondence s emigrantem kádrovou skvrnu. O tom jsem tehdy nepřemýšlel, už proto, že četba Tichého dopisů byla nesmírně zajímavá. Byl jsem na shromažďování korespondence lajdák. Moje krátkozrakost zavinila, že se z této korespondence zachoval nepatrný zlomek. Dopis, který následuje, je ovšem obzvlášť zajímavý, a to z následujícího důvodu: Tichý měl už od šedesátých let – ještě v Československu – v hlavě zárodky svého přístupu k logice a logické analýze přirozeného jazyka (svědčí o tom jeho stati v tehdejším Filosofickém časopise, zejména stať „Smysl a procedura“ z r. 1968). Dopis, který zde uveřejňujeme, má však hodnotu historického dokumentu. Jde o první ´neformální´ formulaci jeho pojetí tzv. konstrukcí a jeho postoje k logice, což se postupně promítlo do systému Transparentní intenzionální logiky (TIL), vyloženého souvisle v monografii The Foundations of Frege´s Logic, vydané asi 13 let po tomto dopisu. Ze vzhledu dopisu je patrné, že byl psán na psacím stroji, což v těch letech bylo standardní. Musíme omluvit překlepy (ostatně to byl osobní dopis), pokud jde o nespisovnosti, vím, že Tichý ovládal češtinu velmi dobře, ale dával přednost psát přirozeně, blízko k hovorové češtině. Jistě připustíte, že jeho jazyk je zde velmi živý a že úpravy směrem ke spisovnému jazyku by narušily kouzlo bezprostřednosti a jistého emocionálního zaujetí, které z dopisu vyzařuje. Tichý posílal mně a Pavlovi Cmorejovi i nadále jednak osobní dopisy, jednak rukopisy svých statí, takže jsme měli výhodu být účastni procesu budování TIL, kterou oba (a dnes už nejenom my) pokládáme za podstatný přínos ke světové logice. --Pavel Materna. (shrink)

The article offers a rigorous explication of the intuitive notion of verisimilitude, I.E., Of the distance of a theory from the truth. The proposal is defended against charges of material inadequacy made by popper, Niniluoto, And miller.

[The Tractatus in the Light of Intensional Logic. ].

The paper deals with the semantics of mathematical notation. In arithmetic, for example, the syntactic shape of a formula represents a particular way of specifying, arriving at, or constructing an arithmetical object (that is, a number, a function, or a truth value). A general definition of this sense of "construction" is proposed and compared with related notions, in particular with Frege's concept of "function" and Carnap's concept of "intensional isomorphism." It is argued that constructions constitute the proper subject matter of (...) both logic and mathematics, and that a coherent semantic account of mathematical formulas cannot be given without assuming that they serve as names of constructions. (shrink)

The article offers a rigorous truth condition for subjunctively conditional statements. The theory is framed in the system of transparent intensional logic and takes connections (especially the cause-Effect relation) as basic. Counterexamples are given to rival theories based on the notion of world similarity.

The vision informing 20th Century philosophy has been aptly described as one of a desert landscape. Philosophers behave as if in expectation of an ontological tax collector to whom they will owe the less the fewer entities they declare. The metaphysical purge is perpetrated under a banner emblazoned with Occam’s Razor. But Occam never counselled ontological genocide at all cost. He only cautioned against multiplying entities beyond necessity His Razor is thus in full harmony with the complementary principle, known as (...) Menger’s Comb, which cautions against trying to do with less what requires more. The two methodological precepts are just two sides of the same coin. (shrink)

In his article "world and essence" ("phil. Rev." 1970, Pages 461-492) plantinga submitted that (a) individuals have essences and (b) the essence of an individual is a non-Trivial property which can be completely known only to god. In my note it is shown that on plantinga's own definitions each individual x has exactly one essence, The trivial property of x-Identity. Thus (b) fails.

It is widely held that oblique contexts and indexical terms present difficulties to Frege's theory of sense. The aim of the present paper is to show that a simple device involving no revision of Frege's semantic doctrine resolves all the alleged difficulties. A simple extension of Frege's notation is proposed which makes it possible to translate oblique contexts into the concept script.

It is widely held that oblique contexts and indexical terms present difficulties to Frege's theory of sense. The aim of the present paper is to show that a simple device involving no revision of Frege's semantic doctrine resolves all the alleged difficulties. A simple extension of Frege's notation is proposed which makes it possible to translate oblique contexts into the concept script.

[Construction as a Subject of Mathematics.].

Pavel Tichy (1936-1994) was a Czech philosopher who originally studied and worked at Charles University in Prague, and spent the second half of his life in New Zealand as a political refugee. Early in his career he invented intensional logic, simultaneously with Richard Montague, but published his version in 1971, slightly after Montague's 1970 papers, and has never been recognised for this achievement. But this was only the beginning of his work. He developed a highly original theory of semantics (...) called Transparent Intensional Logic, which is the basis of an important research program based in the Czech Republic and Slovenia. He published a wide range of original work in semantics, philosophy of logic and language, philosophy of science, and metaphysics; but despite the indisputable quality of this work, he has gained little contemporary recognition. This article provides a brief introduction to his work, focussing mainly on basic ideas of his intensional semantics and his theory of 'constructions'. (shrink)

On the one hand, Pavel Tichý has shown in his Transparent Intensional Logic (TIL) that the best way of explicating meaning of the expressions of a natural language consists in identification of meanings with abstract procedures. TIL explicates objective abstract procedures as so-called constructions. Constructions that do not contain free variables and are in a well-defined sense ´normalized´ are called concepts in TIL. On the second hand, Kolmogorov in (Mathematische Zeitschrift 35: 58–65, 1932) formulated a theory of problems, using (...) NL expressions. He explicitly avoids presenting a definition of problems. In the present paper an attempt at such a definition (explication)—independent of but in harmony with Medvedev´s explication—is given together with the claim that every concept defines a problem. The paper treats just mathematical concepts, and so mathematical problems, and tries to show that this view makes it possible to take into account some links between conceptual systems and the ways how to replace a noneffective formulation of a problem by an effective one. To show this in concreto a wellknown Kleene’s idea from his (Introduction to metamathematics. D. van Nostrand, New York, 1952) is exemplified and explained in terms of conceptual systems so that a threatening inconsistence is avoided. (shrink)