第 16 条 · 正量与负量

Hence it is absolutely necessary to consider what sign is prefixed to each number: for in Algebra, simple quantities are numbers considered with regard to the signs which precede, or affect them.

因此，必须特别注意每个数前面带着什么符号；因为在代数中，简单量就是连同前置符号一起考察的数。

Farther, we call those positive quantities, before which the sign + is found; and those are called negative quantities, which are affected by the sign -.

进一步说，前面有 + 号的量叫正量；受 - 号影响的量叫负量。