Itō Jinsai

Itō Jinsai: The Merchant's Son Who Argued With a Dead Emperor of Philosophy

For nearly five hundred years, the Chinese philosopher Zhu Xi's interpretation of Confucius had stood as unquestioned orthodoxy across East Asia, taught in schools and enforced by governments as the correct reading of the classical texts. In seventeenth-century Kyoto, a merchant's son who had walked away from the family business to study on his own concluded, quietly but systematically, that Zhu Xi had gotten the Analects wrong — and built a school of three thousand students to say so.

A Reluctant Merchant

Itō Jinsai was born on August 30, 1627, in Kyoto to a merchant family headed by Itō Ryōshitsu. He began studying Chinese texts early and, like most educated young men of his era and background, first devoted himself to the philosophy of Zhu Xi, the Song-dynasty Chinese scholar whose systematic reworking of Confucianism — organized around the paired concepts of ri (principle) and ki (material force or generative energy) — had become the dominant intellectual framework across China, Korea, and Tokugawa Japan. By around age ten he was already studying under his uncle, a physician who had treated Emperor Go-Yōzei, and he is thought to have studied further with the Kyoto Neo-Confucian scholar Matsunaga Sekigo.

At twenty-eight, illness forced Jinsai to abandon the family business entirely. The forced retreat became an intellectual turning point: during his period of reclusion he studied Buddhism and Daoism directly rather than secondhand through Neo-Confucian polemics against them, and in the process began to develop serious doubts about the philosophical framework he had inherited. He marked the shift by changing his own pen name to one reflecting a personal commitment to jin, or humaneness — the central Confucian virtue he would spend the rest of his career trying to recover in what he considered its original, unadorned form.

Founding the Kogidō

In 1662, Jinsai established a private academy, the Kogidō, on the east bank of Kyoto's Horikawa River. The school drew what contemporary accounts describe as roughly three thousand students across his lifetime, recruited from a strikingly broad range of social classes and professions rather than the narrow scholar-official elite that Neo-Confucian academies typically served — evidence that Jinsai's teaching reached well beyond the philosophical establishment he was quietly dismantling. After his death, leadership of the school passed to his son, Itō Tōgai, who carried the family's interpretive tradition forward into the following generation.

Rebuilding Confucianism From the Ground Up

Jinsai's central philosophical project was a systematic dismantling of Zhu Xi's metaphysical architecture. Where orthodox Neo-Confucianism held human nature to be identical with universal principle (ri) and therefore inherently, uniformly good, Jinsai rejected the ri-ki dualism altogether in favor of what philosophers describe as an ostensible monism of ki: he treated ri as, in his own words, a "dead word," an abstraction disconnected from actual human vitality, and preferred instead the term michi (the Way) as a "living word" reflecting dynamic, lived human activity. He redefined human nature not as universal principle but as kishitsu, individual physical disposition — a formulation that openly acknowledged the real, observable diversity of human character, from good to bad, rather than insisting on a uniform goodness that plainly did not match everyday social experience.

For Jinsai, the Confucian Way was natural and universal, grounded not in metaphysical speculation but in ordinary ethical conduct within daily life, possessing an inherent vitality independent of anyone's belief in it — a direct contrast, in his framing, with Buddhism, which he argued existed only through its adherents' reverence and produced no comparable practical benefit. He held that humaneness and righteousness were not achieved by suppressing human passions and moral sentiments, as Buddhist and some Neo-Confucian practice recommended, but arose necessarily from them; the mind, in his account, was properly understood as the seat of moral sentiment giving rise to virtuous action, not an empty vessel to be purified of feeling.

A Philologist's Method

Jinsai pursued this reconstruction through painstaking philological analysis rather than pure metaphysical argument. His major work, the Gomō jigi (1705), "The Meanings of Philosophical Terms in the Analects and Mencius," worked systematically through key Confucian terms to strip away what he saw as centuries of Buddhist-influenced vocabulary and later commentarial distortion, aiming to let students recognize the original lineage of each concept and grasp its meaning without the errors accumulated by intervening tradition. He argued that the Analects and Mencius, not the Great Learning favored in Zhu Xi's curriculum, should form the essential core of Confucian education — a direct challenge to the orthodox teaching sequence of his day. Related works, including the Dōjimon ("Questions from Children") and the Daigaku teihon ("The Established Text of the Great Learning"), extended the same method across other core texts.

Despite the ferocity of his critique of Zhu Xi, Jinsai remained, in the judgment of later scholars of Japanese philosophy, fundamentally a figure working within the Confucian tradition rather than outside it — his engagement with ki-ri metaphysics was too systematic and too serious to read as simple rejection, making him, in one modern assessment, "an exemplary Neo-Confucian" reinterpreting the tradition from within rather than abandoning it. He is conventionally grouped with the kogaku, or "Ancient Learning," movement alongside contemporaries such as Ogyū Sorai, though his actual relationship to that movement was more complicated than the label suggests: Sorai, in works including the Bendō and Benmei (1728), became Jinsai's single harshest critic, even as both men shared a commitment to reading the classical texts on their own philological terms rather than through Song-dynasty commentary.

Death and Afterlife

Jinsai died on April 5, 1705, in Kyoto. His teaching flourished especially in Kyoto and the wider Kansai region through the remainder of the Tokugawa period, and his interpretive framework found an institutional afterlife at the Kaitokudō, a merchant academy in Osaka whose scholars later defended his philosophy against Sorai's continuing attacks — a fitting continuation, given that Jinsai's own school had drawn so heavily from merchant and commoner students in the first place.

Why Itō Is Called a Genius

The case for Jinsai's genius rests on the rare combination of philological precision and metaphysical courage: working essentially alone in seventeenth-century Kyoto, he built a systematic, internally consistent alternative to a five-century-old philosophical orthodoxy enforced by the Tokugawa state itself, using close textual analysis of the classical Confucian corpus rather than mere assertion, and did so persuasively enough to attract roughly three thousand students across a remarkably wide social range and to remain a live reference point for philosophers on both sides of the debate — his own defenders and his fiercest critic, Ogyū Sorai — for the following century. Even a modern academic reference work as measured as the Stanford Encyclopedia of Philosophy credits him with exemplifying "the critical spirit inherent in Neo-Confucianism itself," treating doubt as a precondition of philosophical progress rather than a threat to it. The honest counter-case is that Jinsai did not, in the judgment of the same scholarship, step outside the Confucian tradition to invent something wholly new; his innovation was one of interpretation and reconstruction within an existing framework rather than the founding of an entirely separate philosophical system, and his own tolerance toward Buddhism in private correspondence reportedly unsettled more doctrinaire followers, suggesting a thinker whose conclusions were more fluid and provisional than the systematic architecture of his published works implies.

Legacy

Jinsai's kogigaku, or "study of ancient meanings," established a philological model of Confucian scholarship that shaped Japanese intellectual life well into the Meiji era, and his direct textual challenge to Zhu Xi orthodoxy helped open space for the broader current of independent, text-critical Confucian scholarship that flourished across Tokugawa Japan in the century after his death — including the very rival, Sorai, who spent much of his career trying to refute him.

Achievements

• Notable work: Dōjimon