A later generation of Mohists, writing probably in the third century BCE, built something no other Warring States school attempted at the same scale: a systematic reference work of definitions and demonstrations known as the Mohist Canons, preserved as a difficult, compressed layer inside the Mozi alongside the ethical and political chapters the first article describes. The Canons work through logic, defining terms for necessity, sameness, part and whole, and epistemology, distinguishing kinds of knowing by hearsay, by explanation and by personal experience, with a rigor that later historians of Chinese thought treat as the closest surviving parallel to the logical projects of Greek and Indian philosophy in the same era.
The Canons did not arise from disinterested curiosity. Mohism's ethical claims, that impartial care is better policy than graded love, that elaborate funerals waste a state's resources, had drawn sustained attack from rival disputers, the thinkers later grouped as the School of Names prominent among them, and much of the Canons reads as a toolkit built to make Mohist argument precise enough to survive that kind of challenge, along with entries on geometry, optics and simple mechanics that suggest the same circle also pursued natural philosophy for its own sake. The same corpus preserves direct engagement with the White Horse argument associated with Gongsun Long, treating it as a puzzle to be solved rather than admired, which is as close as any Warring States text comes to one school reviewing another's logic in writing.