The Meaning of "Moths Flying into the Flame," Why Moths Fly into Fire, and the Second Half of the Xiehouyu

Moths belong to the insect order Lepidoptera and are mostly active at night, liking to gather in bright places, hence the folk saying “a moth flying into the flame burns itself.” So what does moths flying into the flame mean? Why do they fly into fire? What is the second half of the xiehouyu "moths flying into the flame"?

A moth is a general term for insects closely related to butterflies; both belong to the order Lepidoptera. At rest, most spread their wings flat on either side of the body, and the wings bear eye-like patterns that can deter enemies. They are mostly active at night and like to gather in bright places.

What does "moths flying into the flame" mean?

Meaning one: a moth darting into a flame is a metaphor for bringing about one's own destruction. It comes from The Book of Liang · Biography of Dao Gai.

Meaning two: praise - praising the spirit of people who, for their own ideals and pursuits, press forward without hesitation and defy sacrifice. In today's literary world, where love themes prevail, the moth is used more to express the sentiment of relentlessly pursuing a lover and still refusing to give up even after tasting bitter fruit; it is a solemn and stirring hymn of praise.

Why do moths fly into fire?

Moths belong to the order Lepidoptera. Most moths are active at night; most are nocturnal animals, which shows that moths do not circle lamps because they admire light. Moths have siphoning mouthparts, specialized into a drinking straw, and mainly feed by sucking plant sap. They do not go under streetlights to catch small flying insects, and humans have also ruled out the possibility that moths are drawn to light because of food.

Besides streetlights, campfires in the wild, flashlight beams, household lights, candlelight and some other bright lights also attract moths to circle. Moths are active at night, and when exploring their flight path they use the moon as a “lighthouse.” A moth's eye is a compound eye made up of many simple eyes. When flying, it always keeps moonlight projecting into its eyes from one direction. When it goes around some obstacle or loses its direction, it only needs to turn its body and find the original angle from which the moonlight was projected, and it can continue to feel out its forward direction.

If a lamp appears in the open field, the moth, upon seeing it, cannot tell clearly which is the moon and which is the lamp. Since the moon is far away at the edge of the sky while the lamp is close at hand, the moth mistakes the lamp for the moon. In this situation, as soon as it flies a little past the front of the lamp, it feels that the angle from which the lamp shines has changed —— shining from the side or from behind —— so it turns its body back, until the lamp projects into its eyes at the original angle. Thus the moth keeps turning back and forth toward the lamp, spiraling around it, unable to free itself no matter what.

The second half of the xiehouyu "moths flying into the flame"

Moths flying into the flame —— bringing about their own destruction

The idiom story behind "moths flying into the flame"

During the Northern and Southern Dynasties period, in the Liang dynasty, there was a man named Dao Gai. His parents died when he was young, and he became an orphan, living in great hardship. But he did not shrink back because of this; whenever he had time he devoted himself to hard study, and over time he accumulated a great deal of learning and became a clever and talented man. Dao Gai was bold and straightforward by nature, and was later employed by the court, rising in office all the way to Cavalier Attendant Regular, Palace Attendant, and Libationer of the Imperial Academy.

Dao Gai had a grandson named Dao Jin, who was exceptionally clever from childhood. Dao Gai liked him very much and, whenever he had time, accompanied him in reading and writing poetry, thereby cultivating in Dao Jin the good habit of loving poetry and prose. By the time Dao Jin reached adulthood, his achievements in poetry and prose had surpassed those of Dao Gai, and he won considerable praise from Emperor Wu of Liang. Once, when Dao Gai was chatting with Emperor Wu of Liang, the emperor joked: “Your grandson writes articles so well - your articles must all have been written for you by him, right?”

For this, Emperor Wu of Liang also wrote a poem titled "Lianzhu" and gave it to Dao Gai. The gist of the poem was: “Grinding ink from the inkstone to write articles, you wield the brush with great ease. At such a time you are like a moth flying into the flame, completely forgetting that you yourself may be destroyed. But you are already an elderly man - why not let your grandson Jin write the articles in your place?” Not long afterward, Dao Jin was appointed by Emperor Wu of Liang as Assistant Magistrate of Danyang.

The life cycle of a moth

1. Egg stage: the time from laying to hatching is called the egg stage. After a moth's egg is fertilized, the embryo inside begins to develop, and when the egg matures it becomes a larva.

2. Larva: the larva is the process from hatching out of the egg to pupation, and it is the stage of fastest growth. In some species, body weight increases by as much as ten thousand times from hatching to full maturity before pupation.

3. Pupal stage: the pupal stage is the phase of transition from larva to adult in insects. After the larva matures, its body shortens, it stops eating and moving, its outer surface gradually thickens, and it undergoes pupation.

4. Adult: the adult is the final stage of moth development. It is sexually mature and can mate and lay eggs, but some adults must take supplementary nutrition before mating and laying eggs.

Are moths beneficial insects or pests?

Moths are pests. Moth larvae have chewing mouthparts and feed on plant leaves, making them important pests of agricultural and forestry crops, fruit trees, tea, vegetables, flowers and more. Adults cannot chew food and instead suck tree sap, nectar and so on with a long mouthpart resembling a drinking straw. Some species also form cases or spin silk webs. Some bore into plant tissues to do harm, mining leaf mesophyll and boring into stems. Some invade and damage buds, flowers, seeds and other tissues, sometimes even causing galls. Larvae living in the soil bite and feed on plant roots, becoming important underground pests. Species that harm stored grain, goods, or hides and fur are important warehouse pests. A few species are predatory, preying on aphids or scale insects and the like; for example, Spalgis epius is a natural enemy of the sugarcane woolly aphid.