Abstract: Interdisciplinary, wide-ranging, and flexible, contemporary Japanese legal scholarship is nothing like its antecedents thirty years ago. In significant part, it owes this modern sophistication to tax. More specifically, it owes its inter-disciplinary character to the work of Hiroshi Kaneko. When Kaneko came to Japanese tax law in the late 1950s, he came to a field like most other Japanese legal fields—intellectually isolated, and overwhelmingly doctrinal. Through a novel interpretive theory, Kaneko created a way for tax scholars to debate the economic substance of tax and income. In the process, he (a) created a field (tax law) where little had existed before, (b) brought public finance and the comprehensive tax base to the forefront, (c) kept Japanese public law practice anchored firmly in the rule of law, and yet (d) opened the door to social science in law more generally.