The Logical Analysis Of Verificationist Principle By Arbitrary Public Announcement Logic

Verificationist, an important philosophical sect of analytic philosophy in twentieth century, proposes the watchword of eliminate metaphysics, as they want to clear out research methods without fruit and no differences of opinion from the philosophy. The principle of verification is the core position in logical positivism, because it is the basis of dividing the formal truth and the factual and it is the basis of all the theory of verificationist. At the same time, the principle of verification also is the key point for expose and criticize the verificationist and become the inherent weakness of verificationist. Moore and Fitch trivialize the principle of verification in belief logic and epistemic logic.we choose the correction scheme of Johan.van Benthen’form the many correction scheme by the domestic and foreign experts and scholars. In the correction scheme of Johan.van Benthen’, he interprets "knowable" as "known after an announcement", then builds the axiomatization of arbitrary public announcement logic. We quantify the public announcement by model operator0, so in this setting, Op stands for’there is an announcement after which p is true’, OKp stands for’there is an announcement after which p is known’. So arbitrary public announcement logic is an extension of public announcement logic with a dynamic modal operator that expresses what is true after any announcement:◆Φ expresses that there is a truthful announcement after which Φ is true.On this basis, we define arbitrary public announcement logical original language and the corresponding semantic, and then built the axiomatization of arbitrary public announcement logic and prove its soundness and completeness. Finally, in arbitrary public announcement logic axiomatic system, we logical analysis the principle of verification. First, we define the successful formula and knowable formula, and for knowable formula, we have two types:the th-knowable formula and the wh-knowable formula. Second, we prove the relationship between these definitions, namely then-expressiveness. Finally, we prove the theorem:every formula is wh-knowable.According to the above though, the paper includes five parts:Chapter1introduction involves how the problem is put forward, its background and the main structure of this paper.Chapter2Fitch’s paradox and its correction scheme. First, we introduce the important theorem of verificationist and its principle, and then introduce Fitch’s paradox and moore paradox and their dynamic turn. Finally, we introduce the correction scheme of Fitch paradox, put forward arbitrary public announcement logic.Chapter3arbitrary public announcement logical, we define the arbitrary public announcement logical original language and the corresponding semantic, and then built the axiomatization of arbitrary public announcement logic and prove its soundness and completeness.Chapter4successful formula and knowable formula. First, we define the successful formula and knowable formula, and then we prove the relationship between these definitions, namely their expressiveness. Finally, we prove the theorem:every formula is wh-knowable.Chapter5Summarize the conclusions of this study, and think some ideas and work for further study.