Kogo shinan karakuri 古語指南絡繰 (An Automated Tutor for Old Japanese Languages) is designed to support instruction of classical Japanese (bungo). The tutor helps students prepare for class, but it cannot substitute a human instructor or replace textbook materials such as Haruo Shirane’s Classical Japanese Grammar.
Kogo is not an AI model on its own. It is a set of instructions that can transform any AI model into a useful and friendly tutor. In technical terms, it is a prompt engineering framework; it doesn’t involve costly steps such as training or fine-tuning. In practical terms, it curbs the tendencies of LLMs to overwhelm users with over-explanation and it allows each individual instructor to modify how the tutor works without requiring any technical expertise.
Kogo is being developed by Ariel Stilerman, a textual scholar with a background in psychology and design; Andrew Nelson, an expert in Japanese language studies; and Alan Cheng, a researcher in Human-Computer Interaction in Artificial Intelligence for Education. Special thanks to Pelin Cilgin (EALC), Caleb Langley (EALC), Camilla Piana (EALC), Qianhe Qin (Math), and Sera Wang (CEAS) for early testing and critiquing; and to Ekaterina Mozhaeva (CEAS), Momoyo Kubo Lowdermilk (Language Center), and Carolyn Zou (CS) for early feedback on the technical and pedagogic framework.
The pedagogic approach of kogo is inspired in the work of early Soviet psychologist Lev Vygotsky (1896-1934). Vygotsky argued that between what students can already do on their own and what they cannot yet do, there is a moving zone of what they can do with the help of a guiding expert. This “Zone of Proximal Development” is what later inspired cognitive psychologist Jerome Bruner (1915-2016) to propose the notion of “scaffolding” (Wood, Bruner, and Ross, “The Role of Tutoring in Problem Solving,” 1976). Currently, most college-level courses are designed to tackle this zone of proximal development and to offer scaffolding to students with different prior skills or learning styles.
Kogo was designed to work with students in the paper-thin zone between what they can do on their own and what they can do with the instructor in class. This “Zone of Pre-Proximal Development” is arguably the most promising stage of the learning process to experiment with new approaches. The aim of the tutor is to help students prepare the material to then get the most out of in-class interactions with peers and instructors.
In this example, a student preparing a text for class in the context of a graduate seminar in premodern Japanese literature (JAPAN389, Winter 2026) provides the first sentence of the medieval tale Monokusa tarō and the tutor offers guidance to parse, analyze, and translate.
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Student: ただし名こそ物くさ太郎と申せども
Tutor: Let's begin our analysis with the predicate at the end of the phrase: 申せども (mōse domo). First, what is the dictionary form (shūshikei) of the verb 申せ?
Student: 申す
Tutor: Correct. Now, looking at the combination 申せども (mōse-domo), what is the grammatical function of the particle ども?
Student: It is a concessive, "this but that"
Tutor: That is correct; ども indicates a concessive condition ("although/even though"). Grammatically, what specific conjugation form (katsuyōkei) does ども attach to?
Student: 已然形
Tutor: Yes. Based on the fact that 申す (mōsu) changes to 申せ (mōse) in the Izenkei, what conjugation class (katsuyō) does this verb belong to?
Student: That is irrelevant to me right now. Can we look at the rest of the sentence? I am not sure what it means.
Tutor: We can certainly move to the previous section. The particle と appears immediately before 申せ. In the phrase 物くさ太郎と申せ, what is the function of と?
Student: Looks citational, marking what is said or thought
Tutor: Correct. と marks the content of what is being called or said. What is the grammatical category of the phrase 物くさ太郎 found immediately before と?
Student: speech, thought bubble, or name??
Tutor: Yes, it is a proper name, "Monogusa Tarō". Now, looking left at the particle こそ immediately preceding it: to what category of particle does こそ belong?
Student: It connects to the verb at the end
Tutor: Precisely. Particles that create this binding link with the final verb are known as what type of particle (joshi)?
Student: The professor will likely say this in class, so I am not worried about it. I just don't understand what the koso does. How would the sentence be different without it?
Tutor: It acts as a strong emphatic marker. Given that the sentence ends with ども (although/but), what does emphasizing the 'name' (名こそ) suggest about the reality or substance of the person?
Student: Maybe that their personality doesn't match their name?
Tutor: That is exactly the implication. One final component remains at the very beginning: how does the conjunction ただし function here?
Student: Something like "in fact" or "indeed" but I forget now what this function is called technically
Tutor: It is actually a conjunction functioning as "However" or "But," often used to introduce a proviso or a contrast. Now that we have analyzed each part, how would you paraphrase the full meaning of this sentence?
Student: However, even though his name was Lazy Tarō...
Tutor: That captures the meaning perfectly, recognizing that "Monogusa" means "lazy." Please provide the next section of the text you would like to analyze.
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