Tora Koyama

Yamaguchi University
  •  205
    McTaggart’s paradox and his A-theory and B-theory are basic notions in the contemporary philosophy of time. It is well known that the paradox was introduced by McTaggart’s paper called “The Unreality of Time” published in 1908, so that it has a one-hundred-year history. As for A-theory and B-theory, in contrast, McTaggart himself didn’t consider both of them at all. The notions of A-theory and B-theory came much later, 60 years after the paradox. Moreover, they had not been as popularized as the…Read more
  •  18
    Analytic philosophy in Japan since 2000
    Asian Journal of Philosophy 1 (2): 1-17. 2022.
    Since its inception, analytic philosophy has failed to attain dominance in Japan. However, the 21st century has seen analytic philosophy gain traction among Japanese philosophers. This paper, which examines the status quo of analytic philosophy in Japan since 2000, consists of two parts. The first part deals primarily with organizations—specifically, relevant associations, journals, conferences, universities, and publishers are illustrated. The second part explores key works in each area—namely,…Read more
  •  7
    Editorial Note for the Special Issue
    Annals of the Japan Association for Philosophy of Science 29 57-59. 2020.
  •  123
    Truthmaker Monism
    Annals of the Japan Association for Philosophy of Science 29 61-73. 2020.
    Monism is a metaphysical view according to which there is only one fundamental object. This paper will explore monism within the context of truthmaker theory, or Truthmaker Monism, a view rarely discussed in literature. Although few truthmaker theorists defend monism, at least explicitly, some theories seem to share the spirit of monism to some extent. Interestingly, they are proposed as solutions for the same problem, called the problem of negative truth. A close examination will show that whil…Read more
  •  225
    What is the exact relationship between analytic philosophy and philosophy of science? In this paper, I will address this question from the perspective of research traditions, with the help of recent histor- ical studies on analytic philosophy. The two groups are particularly focused: the Polish philosophers and the logical empiricists in Berlin. Neither of them is unknown to us. However, by taking seriously their connection to the development of analytic philosophy and philosophy of science as r…Read more
  •  15
  •  332
    Modal realism is an ontological position made familiar by David Lewis, according to which there exist possible worlds other than the actual world that we inhabit. It is hard to uphold modal realism, and indeed modal realism has only a few advocates. However, as most contemporary metaphysicians agree, this does not mean that it is easy to refute modal realism. In this paper, I argue against modal realism from a metaontological point of view. First, I provide a precise formulation of modal realism…Read more
  •  278
    Modal realism is an ontological claim according to which there exist many possible worlds just like our actual world. Since it is so hard to believe, modal realism has only a few advocates. However, it is well known that alternative theories have serious problems. It is one of the central issues of metaphysics to find a persuasive way to reject modal realism. In this paper, I will suggest that it could be accomplished with help of metaontology-one of the topics of metaphysics which has recently…Read more
  •  143
    現在主義・時制・Truthmaker
    Journal of the Japan Association for Philosophy of Science 34 (2): 49-59. 2007.
    In this paper, I try to defend Presentism. First of all, I explore how Presentism diverges to its versions and show that none of them, which include the currently standard Presentism that invokes tense logic, are tenable. Next, I point out that some philosophers argue that by replacing the Quinean criterion of existence with the Truthmaker Principle, another version of Presentism, which invokes tensed properties, can emerges. However, this version has a highly implausible conclusion. Finally, I …Read more
  •  155
    The Simple Sentence Puzzle and Ambiguous Co-referential Names
    with Yasuo Nakayama
    Annals of the Japan Association for Philosophy of Science 10 (3): 127-138. 2001.