Philosophical Questions: Connecting with and Expanding into Diverse Fields

2023/02/03

In the Faculty of Letters' Major in Philosophy, you can study a wide range of philosophical fields, from ancient to modern times. My own research focuses on problems related to the philosophy of language and logic. "Language and logic" may sound difficult, but the subject matter is the words we use every day and the meaning and information they convey, and understanding the initial questions is not so hard. For example, we can understand a sentence we've never seen before almost instantly and extract new information from it. It is a wonder, when you think about it, that we can understand language, organize our thoughts, and communicate with others in this way, even though no one has explicitly taught us the rules. One of the problems can be rephrased like this: While there are dictionaries for words, there are no "dictionaries" for sentences formed by combining words, or for longer texts like this one. Why is that? It seems that we don't use language by memorizing each sentence by rote, as in a travel phrasebook, but rather by creating sentences on the spot—improvisationally, so to speak—according to our knowledge of words and some kind of "rules." What exactly are these "rules"? When we think about it this way, it seems truly mysterious that a mere sequence of sounds or characters can mean something, and we find ourselves grappling with questions that have no easy answers, such as: What is meaning in the first place? Where does it reside? How is it possible for something to mean anything at all?

The questions I've raised here are questions in the philosophy of language, but they are also studied in an interdisciplinary manner across a wide range of fields related to the meaning and information of language, including logic and linguistics. In fact, it is no exaggeration to say that the work of philosophers has played a major role in establishing these new fields of research. The logic studied today originates from the research of Frege and Russell, who created one of the main currents of modern philosophy. This work eventually led, through the contributions of figures like Gödel and Turing, to the establishment of modern information science. Furthermore, the fields of linguistics concerned with the meaning of words and communication are called semantics and pragmatics. The ideas of philosophy and logic have played a significant role in establishing what should be discussed in these fields and how, defining their subject matter and methods. My current research straddles logic and linguistics, and I am also tackling new problems in collaboration with people in the fields of information science, particularly artificial intelligence and natural language processing. It can be said that the questions of philosophy are connected to existing disciplines, while at the same time being questions that lie in the boundary areas that do not fit neatly within them.

I myself studied in this Faculty of Letters' Major in Philosophy. I did not choose the Major in Philosophy with a clear outlook from the beginning. At first, I had a vague desire to learn something as fundamental and universal as possible. It seems completely reckless in retrospect, but I was more attracted to fields where it was not yet clear how to achieve what could be called "progress," rather than to fields where methods were already established and the criteria for advancement were clear. I should add that this can be a bit like grasping at clouds, and there is also the approach of starting with more concrete problems and applications and then arriving at philosophical questions. Around that time, Professor Yoshinori Saito of the Major in Philosophy was teaching a class for first-year students at Hiyoshi called "Special Lecture on Humanities" (often referred to simply as "Tokuron"). It had the atmosphere of a seminar experience for first-year students. There, I learned the joy not only of solving problems but also of formulating and thinking about new questions from the most fundamental level—questions that no one else had noticed. Thus, I chose philosophy without any hesitation, became fascinated by the problems of language and logic, and before I knew it, a new intellectual world had opened up to me. In the Faculty of Letters, you can study not only philosophy and logic but also various language-related subjects offered at The Keio Institute of Cultural and Linguistic Studies. In this interdisciplinary environment, I met several professors and learned philosophy (as well as logic and linguistics) as a living experience, different from simply acquiring knowledge from what is written in books and papers. This can be compared to the practice of actually speaking a language or playing music for enjoyment, rather than simply "learning" them. I believe that sharing this "experience of philosophy" will be important for future students of the Faculty of Letters.

*Affiliations, titles, etc., are as of the time of the interview.