The members of a second, still rather small set of characters are generally called “ideographs”, supposedly representing more abstract ideas incapable of being pictured directly. There are two subsets here. The first comprises fairly simple and direct graphs: 一, 二 , and 三 signify 1, 2, and 3 respectively, and 上 and 下 are “above” and “below”, or “high” and “low”. The second subset involves less simple and direct graphs, but they do have much illustrative content. Some famous textbook examples of this category of ideograms are ming, which combines the pictures of the sun 日 and moon 月together to signify the Chinese word for “bright”, 明 (as with English, it also means “intelligent”). Here is a paradigmatic example of the conventionality of the characters. The sun and the moon together do suggest light, illumination, etc. But so would a picture of a candle, or two candles; a fire, or two fires. Many pictures might represent a word, or concept, and consequently, to some extent at least, using sun and moon together for “bright” is arbitrary, the signified cannot be determined unambiguously from the signifier alone; it must become conventional.