Since Liu Beisan Gu Maolu invited Zhuge Liang, the two have always had very good friendships, the relationship between master and servant is harmonious, and Liu Bei has also said: There is Kong Ming in loneliness, and there is water in Juyu. Later, when the White Emperor entrusted himself with isolation, Liu Bei handed over shu and Liu Chan to Zhuge Liang, and also instructed him that if Liu Chan had no talent, he could "take it on his own". Such a harmonious and trusting relationship between kings and subjects was also highly respected by later generations, but did Liu Bei really trust Zhuge Liang like that? If it is true, then why did Liu Chan entrust it to two people? Is Liu Bei uneasy about his auxiliary ability or is he worried that his power is too great? It was true that the White Emperor was entrusted with isolation, but Liu Bei installed a deputy general around Zhuge Liang, named Li Yan, who was later demoted to a commoner by Zhuge Liang.
Grain and grass are very important in a war, and in ancient times, wars followed the principle of "soldiers and horses do not move, grain and grass first", grain and grass are safe and sufficient, which is an important factor in stabilizing the hearts of the army. At that time, Zhuge Liang was on the front line, and Li Yan was almost at the same level as Zhuge Liang, so it was Li Yan who provided logistical support in the rear, and this division of labor was still very good, but because the grain and grass were too important, and the mistakes made by Li Yan were really difficult to forgive, it caused the end of being reduced to a civilian.
Zhuge Liang made many northern expeditions, but failed several times due to the grain and grass problem, so this time Li Yan was responsible for preparing for the transportation of grain and grass, and originally assumed a great responsibility. When Li Yan transported grain, it was precisely the time of summer and autumn socialization, when the rain was sufficient, and the geographical location of the Shu kingdom was rugged and uneven, and it was even more difficult to travel on the mountain road when it rained, so it delayed the transportation of grain, although there was no time and place, but if he and Zhuge Liang knew the truth, Zhuge Liang would not cure him of any major crimes, after all, it was a natural factor and did not concern Li Yan or anything, but people went farther and farther on the road to death.
Li Yan first sent someone to inform Zhuge Liang to retreat, and Zhuge Liang thought that something had gone wrong with the grain and grass, but when Zhuge Liang returned, Li Yan found Zhuge Liang again and said: "The army is spared, why should it return?" Such repeated and upside-down remarks could not make Zhuge Liang not angry, and if he delayed as much as possible, he should have been punished, if Li Yan told the truth, it would have been lightly sent, but he was shirking his responsibility from the beginning, and such repeated remarks changed their nature, became a lie about the military situation, and caused the army to return without success and the Northern Expedition to fail again. Lying about military information and delaying a fighter plane, no matter what dynasty it is in, is a major crime to be beheaded.
Not only that, this Li Yan also deceived the Hou Lord, who knew the reason for Zhuge Liang's withdrawal from the army at that time, and also told the Hou Lord that "the army retreated in disguise, and wanted to lure thieves into battle" If li Yan had no other purpose, it would make people not believe it.
Zhuge Liang assisted the government, and Zhuge Liang remembered that he was also a loyal vassal of Liu Bei's hand-picked Trust, and had meritorious service to the Shu state, so he demoted him to a shuren, and then let his son take his place.
Some people say that Zhuge Liang is doing this to consolidate his position, but his position is not something that Li Yan can threaten, so it is unlikely that Zhuge Liang will attack dissidents, and it can only be regarded as a public affair.