The Rebus Principle

The other day, while reading chapter 12 of Guns, Germs, and Steel, I came across a reference to pun development. 

"...it's easy to draw a recognizable picture of arrow, hard to draw a recognizable picture of life, but both are pronounced ti in Sumerian, so a picture of an arrow came to mean either arrow or life. The resulting ambiguity was resolved by the addition of a silent sign called a determinative, to indicate the category of nouns to which the intended object belonged. Linguist term this decisive innovation, which also underlies puns today, the rebus principle."   Guns, Germs, and Steel by Jared Diamond

The pun reference was mostly insignificant, but it caught my attention   naturally. What Diamond was discussing was the development of early writing systems, particularly logographic writing systems (single symbols representing whole words or morphemes) such as hieroglyphics or even Chinese script. The rebus principle is the use of preexisting symbols purely for their pronunciation regardless of their meaning in order to represent abstract subjects such as "love" or "belief"; it is easy to depict a physical entity with symbols, but very difficult to depict a concept or emotion with symbols. Therefore, symbols representing physical entities were often strung together in order to represent abstract concepts. It's very much like Pictionary: to represent "I can see you" one would write   or draw   "eye-can-sea-ewe." Similarly, puns use the rebus principle for the simple pleasure of exploiting a highly limited writing system or language to appear funny   a mere matter of opinion   or clever   also a mere matter of opinion.