The first line of Small Preponderance (King Wen 62) is drawn as yin, the numeral six in the old divination manuals. James Legge's translation renders the line as a bird flying upward, and there will be evil. The image sits inside a hexagram whose judgment as a whole concerns progress and attainment, but advantage in being firm and correct; small affairs may be undertaken but not great ones, as with a bird flying past that leaves its cry behind, for whom it is not fitting to ascend but only to descend, and there great good fortune, and this line supplies one stage of that larger reading rather than a complete statement on its own.
Structurally the line stands at the lowest place of the lower trigram Gen, mountain in Legge's readings of the eight trigrams, while the upper trigram of the hexagram is Zhen, thunder in the same traditional set of images. The Great Symbolism of the hexagram reads thunder above a mountain; the superior man in his conduct exceeds a little in humility, in mourning exceeds a little in sorrow, and in expenditure exceeds a little in economy, and the first line takes its place inside that combined picture of Gen below and Zhen above.
Read on its own the line neither opens nor closes the hexagram's argument. It marks the point where Gen is either forming (in the lower trigram) or completing itself (in the upper), and later interpreters treat its image, The Bird Flying Upward, as the concrete case through which the hexagram's abstract judgment becomes visible in a single situation rather than a general principle.