Canons: definitions

Introduction

This week begins four weeks on the Canons: Canons I and II and their two Explanations. They are the strangest part of the Mozi, probably written a generation or two after him, and shaped like a dictionary bound to a textbook. Each Canon is a very short definition or proposition; the Explanation comments on it. For two thousand years almost nobody could read them. Only after Sun Yirang reordered the text in the late nineteenth century did scholars find logic, geometry and physics inside.

This week covers the definitions in Canons I. The opening entries lay the foundation. "故 (reason): that which, being had, a thing then comes to be." "体 (part): what is divided off from a whole (兼)," the same 兼 as in impartial care. "知 (knowing): a capacity." Then a run of ethical terms, each defined through benefit. "仁: care taken individually." "义: benefit." "礼: respect." "孝: benefiting one's parents." "信: words matching intention." "功: benefiting the people." "赏: a superior repaying an inferior's achievement." "罚: a superior repaying an inferior's offence." Further on come same and different, praise and blame, and the ruler: "君: what ministers and people jointly agree upon."

Then the geometry. "平 (level): of the same height." "中 (center): same length to all." "端 (point): the part that has no order and is foremost." "圜 (circle): one center, same lengths." "直 (straight): in line." "方 (square): four sides and corners." These are roughly contemporary with Euclid, with no contact between them.

Why 墨门 / The Mohist Community reads the Canons is simple. A tradition that defines achievement as benefiting the people and the ruler as a joint agreement deserves to have its way of thinking learned.

The three tests

Definitions are not claims, and the three tests test claims. But the definitions in Canons I are far from neutral. "义: benefit" is not dictionary-making; it puts the whole of ethics on the foundation of the third test, use. That raises this week's question: can a definition be tested? The Community's view is that definitions are judged by use. A good definition is one that makes later discussion clearer and less quarrelsome. The geometric definitions, such as "circle: one center, same lengths," really do rest on the second test: draw one with a compass and see.

For families

• 科技堂: draw a circle with string and a pin and explain "one center, same lengths." Then ask how to find the center of a circle you are given.
• "A part is divided off from a whole": split an orange, talk about parts and wholes, then explain that the 兼 of impartial care is this whole.
• Have the children write a definition of "friend" and "fair" in ten words or fewer and vote on the best.

For chapters

• 20 min reading · 20 min 墨辩 · 10 min 三表 review · 10 min 职 reports.
• 墨辩 motion: "The definition '义 is benefit' oversimplifies morality." One side cites Canons I; the other cites the Confucian distinction between rightness and profit.
• 三表 review: bring "the ruler is what ministers and people jointly agree upon" into the present. Where does the authority of the 墨门理事会 and the chapter lead come from? Read alongside the relevant clauses of the 墨者之法.