“Sen-mon-ka” to ha dare ka (Who Is an "Expert"?)

The crisis of expertise is a defining problem of our time. Pandemics, climate change, wars, and upheavals in the established order follow one after another; each time, countless "experts" emerge whose views frequently diverge and sometimes flatly contradict one another. Even in affluent democracies, authoritarian-leaning governments have arisen that dismiss scientific consensus in favor of political expediency. Small wonder that so many people no longer know what—or whom—to believe. This volume brings together scholars from the history of science, philosophy of science, media studies, science and technology studies, history, and academic publishing to address that disorientation from multiple angles.
 
Because the book is written in Japanese, clarifying the conceptual vocabulary is itself part of the argument. The Japanese term sen-mon, commonly used to render "expert," etymologically descends from a classical Chinese expression meaning "to be versed in a single scripture." The character mon carried the sense of receiving instruction from a master. Sen-mon thus carries a strong connotation of deep but bounded specialization—someone whose very identity is tied to one fixed domain. The English word "expert," by contrast, foregrounds experience and mastery; the breadth or narrowness of one's vision is, at most, a secondary consideration. The two terms have evolved along different conceptual paths, yet they are constantly folded into one another through translation—a tension the book keeps in view throughout.
 
Decomposing the word in this way immediately sharpens the central question: what, exactly, makes someone an expert? In my own chapter I approach this historically, tracing when and how institutions came to authorize certain individuals to deliver technical judgments that policymakers and courts would accept as binding. What this history reveals is that expertise is never established by knowledge alone; it depends equally on a community of practitioners and on a broader society willing to extend its trust. Constructing and sustaining that mutual trust—through credible narratives, transparent procedures, and genuine accountability—therefore becomes as important as the knowledge itself.
 
A second major thread running through the volume is the structural relationship between sen-mon (specialization) and kyo-you (general or humanistic education). The question of what kyo-you should look like is, in this sense, an implicit counterpart to every discussion of expertise. A specialist who lacks the courage to engage beyond their own domain risks the characteristic errors of tunnel vision; what is needed is the willingness to intervene, carefully, in adjacent territory. For citizens navigating a deluge of information, meanwhile, a "negative literacy"—the capacity to tolerate ambiguity and suspend judgment rather than reaching for premature certainty—may be more valuable than any specific body of knowledge for resisting disinformation and propaganda.
 
The volume also confronts an uncomfortable history: the development of both sen-mon and kyo-you was bound up with social hierarchy and contributed to entrenched gender inequality. Professional sen-mon education in science, engineering, law, and economics was effectively reserved for men, while kyo-you bifurcated into a cultivating Bildung for young men and a decorative cultural accomplishment for young women—a preparation, essentially, for marriage rather than for public life. That structure has largely collapsed, but it left both terms diminished in the process.
 
Readers may note that the seismic impact of generative AI, still nascent when this book went to press, receives little direct treatment. Yet this is precisely why the book's core argument feels more urgent now than when it was written. When a near-invisible black-box mechanism delivers knowledge directly to citizens, understanding how expertise functions—and how societies come to trust or distrust it—is not an academic luxury. It is a civic necessity.
 

(Written by OKI Sayaka, Professor, Graduate School of Education / 2026)