QA回答：什么因素导致了秦朝的灭亡？

Feng xian
The direct reason was its military defeats.

直接原因是军事上的溃败。
原创翻译：龙腾网 https://www.ltaaa.cn 转载请注明出处

All other problems, such as political brutality and cultural integrations, can be solved as long as the Qin army held its ground and defeated the rebels. Those problems indeed contributed to the fall of the Qin dynasty but they were not the direct cause.

只要秦军能坚守阵地并镇压叛乱，其他诸如政治暴虐或文化融合等问题均可解决。这些问题确实加速了秦朝的灭亡，但并非直接诱因。
原创翻译：龙腾网 https://www.ltaaa.cn 转载请注明出处

In short, the elite of the Qin army was divided into two parts, the northern and the southern armies. The Northern units commander Meng Tian was ordered to suicide due to the political struggle. Since the rebellion and uprising against the Qin dynasty began, the northern army led by the vice commander Wang Li was pulled back and fought the rebels.

简而言之，秦军精锐分为南北两部。北军主将蒙恬因政治斗争被逼自尽。叛乱爆发后，副将王离率北军回师镇压。

Yet in one of the greatest battles possibly in the history of the world that was impossible to lose in 999 of 1000, the northern army with the legacy of defeating the xiongnu army and conquered the Eastern Kingdoms, was completely wiped out by xiang Yu’s army. 200,000-300,000 Qin soldiers were either killed or buried alive after they surrendered. xiang Yu historically was considered the greatest general in the East.

然而在这场千载难逢的战役中（胜率本应高达99.9%），曾击溃匈奴、横扫六国的北军竟被项羽全歼。20-30万秦兵投降后遭屠杀或活埋。项羽由此被后世奉为东方第一战神。

Then for the southern army which was responsible for colonisation led by the commander Zhao Tuo, it however completely cut off the connection with China, remained neutral and isolated from the wars and conflicts.

而负责开拓南疆的赵佗所率南军，却选择断绝与中原联系，保持中立置身事外。

Hence, what was left for the Qin dynasty was no more than a group of prisoners and poorly trained security guards. They naturally cannot withstand and even protect their own homeland (the original Qin Kingdom) from the outside forces. It was a matter of time for the Qin core areas to be conquered. Eventually, Liu Bang and xiang Yu broke into the capital one by one and the Emperor was killed and the palace burned into ashes by xiang Yu.

此时秦廷仅剩囚徒与杂役组成的乌合之众，连故土（原秦国疆域）都无力守卫。核心地带沦陷只是时间问题。最终刘邦项羽先后破城，秦帝遇弑，宫阙尽焚。

That was the direct cause of the fall of the Qin dynasty.

此即秦亡之直接因果。

Stone Chen
The collapse of Qin dynasty was primarily a result of the systematic malfunction of its legalistic political ideology in the new imperial environment.

秦之崩溃本质是其法家治国体系在帝国新环境下的系统性失灵。

Prior to Qin’s conquest and unification of China, its legalistic system, which was established back in 4th century BCE under Shang Yang’s reforms, had worked noticeably well due to the Qin’s relatively small population and landmass.

商鞅变法（公元前4世纪）确立的法度在统一前运转良好，因秦国当时地狭人稀。

Qin’s land was far less fertile than the floodplains of lower Yellow River, hence the number of inhabitants Qin’s lands could sustain was severely limited. Even after Qin’s conquest of the rich soils of Ba and Shu (i.e. present-day Sichuan), we observe no considerable surge in its population until mid 3rd century BCE.

关中土地贫瘠远逊黄河下游，承载力有限。即便吞并巴蜀沃野（今四川），至公元前3世纪中叶人口仍无显著增长。

The small population made it possible for the state to rigorously carry out Shang Yang’s draconian penal codes and execute the laws as stated. Within the small state boundary of 4th and early 3rd century BCE Qin, these laws, as harsh as they were, were largely practical because of the simplicity of mobilizing a small population towards a single fixed goal — uniting the country. Drafting was conducted according to the level of income of each household and conscxtion was usually carried out less hastily than other contemporary states. (Below: East Asia circa 350 BCE)

小国寡民使严刑峻法得以落实。在有限疆域内，虽法令苛刻，但动员民众实现"统一"单一目标切实可行：按户等征调，节奏较他国从容。（下图：公元前350年东亚局势）

These all changed fundamentally when Qin transformed from a regional kingdom into a centralized empire. Firstly, its nation-building goals became diversified — it now face at least three immediate challenges that need to be addressed with efficiency and caution:

当秦国升级为中央集权帝国，一切剧变：建国目标多元化，需同时应对三大急务——

The necessity of a unified domestic market, on which Qin Shi Huang launched a series of standardization efforts targeting currency, weights and measures, writing system, even thoughts and philosophy.

构建统一国内市场（秦始皇推行货币、度量衡、文字乃至思想的标准化）；
原创翻译：龙腾网 https://www.ltaaa.cn 转载请注明出处

The prospect of civil disobedience in conquered areas, and its potential of intensification. As a measure of precaution, Qin Shi Huang confiscated all civilian arms and shipped all weapons to the capital, xianyang. This was hardly an effective move because uprisings in ancient China didn’t necessarily need manufactured arms and ammunitions — club-wielding warriors and donkey-riding knights were all welcomed.

防范六国遗民叛乱（收缴民间兵器运往咸阳，然起义军本就不依赖制式武器——木棍驴骑皆可成军）；

The threat from surrounding nomads, namely xiongnu and Baiyue. In the past, borderland states like Yan, Zhao, and Chu all accumulated plenty of experience of dealing with nomadic incursions in a cost-effective way. When Qin took over, it lacked such experience and was forced to combat the problem using the only option left — military conquest. In total Qin deployed over a million troops to the frontier (this included the troops deployed for the construction of the Great Wall, which was also meant to be a defensive measure against xiongnu) and thus left its heartlands virtually undefended. (Below: East Asia in 221 BCE after Qin’s unification of China)

抵御胡越边患（燕赵楚原有低成本御胡经验，秦却只能军事征服：百万大军戍边修长城，致腹地空虚）。（下图：公元前221年秦统一后的东亚）

We know that the Dazexiang uprising of 209 BCE marked the beginning of the collapse of Qin Empire; the uprising, however, was not some desperate attempt made by cornered animals, rather it was directly caused by Qin’s harsh laws which mandated the execution of anyone who showed up late for obligatory work assignments.

大泽乡起义（前209年）虽敲响丧钟，但非困兽之斗——其直接诱因正是"失期当斩"的严苛律法。
原创翻译：龙腾网 https://www.ltaaa.cn 转载请注明出处

Chen Sheng, one of the leaders of the revolt, was ordered to march over 1,000 kilometres north to the northern frontier with a band of several hundreds of peasants. One would ask, how come there were no recorded revolts before Qin’s unification of China if its laws were that harsh and inhumane?

义军领袖陈胜本需带数百农夫北上戍边千里。若秦法向来残暴，为何统一前无大规模起义？

Like what I’ve explained previously, in the tiny state of Qin where "frontier" literally meant a series of defensive forts and towns on the eastern border with a total length of under 300 km, Qin’s laws were largely executable because of the high degree of predictability. In the new environment where Qin’s population suddenly septupled and its land more than quadrupled, the old legalistic order can no longer work as expected. Even worse, it acted as a catalyst for the fall of the empire.

如前所述：统一前秦国疆域狭小，"边境"不过三百里防线，法令因可控性强而可行。待疆域扩四倍、人口增七倍，旧法体系必然崩坏，反成催命符。

Ayanga
There are many factors that contributed to the fall of Qin, such as:

秦朝的覆灭有多重因素，例如：

incompetent Second Emperor - unlike the First Emperor, the Second Emperor was stupid and he relied on Zhao Gao to make decision. On the other hand, Second Emperor wanted to show his people that he’s competent. Therefore, he insisted to continue the projects such as the construction of Epang Palace, without trying to slow it down to ease the economy burden; as suggested by Li Si and other competent ministers.

秦二世昏庸无能——与秦始皇不同，他愚钝且依赖赵高决策。同时，他又急于证明自己，因此不顾李斯等贤臣劝谏，执意继续阿房宫等工程，不肯放缓以减轻经济负担。

Qin laws were very strict, but then the Second Emperor made the law even stricter to make his people know that he’s powerful - a very bad move. Especially he didn’t have competency like his father. The law was okay and acceptable for the Qin people who had already used to Legalism and meritocracy system that had been applied in Qin a century earlier. But after the unification and the Qin laws were applied to the whole former states, many people could not accept it.

秦法本已严苛，而秦二世为彰显权威，竟进一步加重刑罚——此举极其愚蠢，尤其在他缺乏其父才能的情况下。秦人因百年来已适应法家体制，尚能接受严法；但统一后，六国遗民对此难以容忍。

Qin laws were very details and strict. For example, there should be a supervisor to check the quality of harvests that was sent to granaries; when the farmer were harvesting, they were not allowed to drink wine, etc. Although the law was actually for the benefit of people, yet it’s too detail and for the people from other states, the laws probably different from their customs. Therefore many of the people (especially aristocrats and noblemen) from the other former six states resented Qin so much.

秦法细致入微，例如：粮食入仓需专人监察，农民收割时禁酒等。虽本意是为民生，但过于琐碎，且与六国旧俗相悖。故六国贵族及百姓对秦怨愤极深。

The economy burden. Li Si asked the Second Emperor to relax the tax and not to continue or slowing down the construction of Epang Palace, Great Wall, and the mausoleum. But instead of slowing down or discontinue, the Second Emperor forced more labor to fasten the project and raised the tax.

经济重负。李斯曾劝秦二世减税、停建或缓建阿房宫、长城及陵寝，但二世反增徭役、加赋税以加速工程。

When Hu Hai illegally took the throne, he killed First Emperor’s sons and daughters. Also, he killed many important loyal military officials such as Meng Tian and Meng Yi. These made some loyal officials demotivated and either they were resigned, or they were killed by Hu Hai and Zhao Gao. Therefore, just two years after the First Emperor’s death, only sycophants and flatterers who still in their positions. And these peoples concealed rebellions that were done by peasants in many areas. As a result, the damages were irreversible.

胡亥篡位后，屠戮始皇子女，并诛杀蒙恬、蒙毅等忠臣良将，致使贤臣或隐退或被害。始皇死后仅两年，朝中只剩谄媚之徒，他们隐瞒各地民变，终致局势无可挽回。

Zoe Wu
When Qin attacked the six countries, The strategy adopted by the State of Qin was to occupy the population , land and food in the occupied place,and using these resources to constantly expand to obtain more abundant land and population,Collect local taxation and plunder the official wealth,maintain the economic balance of the empire ,and ensure the military logistic.

秦灭六国时，采取“占其地、夺其民、掠其粮”之策，以战养战，通过征税与抄没贵族财富维持帝国经济与军需平衡。

After the unification of the six states,the Qin State didn't stop the war, it aimed at the Nanyue and the xiongnu. In 219 B.C. ,the Emperor of Qin launched 500000 troops,Which took 5 years to occupy the Nanyue . In 214 B.C. , Qin Shihuang launched 300000 troops to expel the huns and recover the Hetao area. Although the State of Qin recovered the Nanyue and xiongnu , They are both exotic places and paid very little for their population and land, Which could not make up for the expenditure brought about by the war.

统一后，秦仍未止战，南征百越（前219年发兵50万，耗时五年）、北击匈奴（前214年遣30万夺回河套）。虽取胜，但两地人稀地贫，远不足以弥补战争消耗。

And to calm the soaring bureaucratic costs of the six countries, and caused the financial problem to be prominent.

同时，为镇压六国故地，官僚成本激增，财政危机凸显。

And after the unification of the six countries, the war reduced and idle personnel increased, the government absorbed excess labor through large-scale infrastructure(such as the Great Wall 、Epang Palace、mausoleum). However, the government could not generate income by using such infrastructure. In a short period of time, there was no income.The financial expenditure on infrastructure is rigid, which formed the black hole of financial.

统一后战事减少，闲散人员增多，朝廷以长城、阿房宫、陵寝等工程吸纳劳力。但这些基建无法短期创收，刚性支出形成财政黑洞。

The government increased the agricultural tax in order to make up for the financial deficit. The official oppressed the peasant，leading to the peasant uprisings, the government cracked down everywhere, the imbalance of financial became more and more serious.

为弥补赤字而加征农税，官吏欺压百姓致民变四起，镇压行动又加剧财政失衡。

Another secondary the factor is that the Dynastic of Qin didn't do good job in the construction of spiritual civilization, the stability of a regime, the ideological construction is dispensable. The foolish people though of the Qin State trained the peasant into plating machines, the State of Qin was originally a barbarian land. This set was suitable for the people of the Qin State, but not suitable for the people of the six countries.

另一关键败因是精神文明建设的缺失。秦人将民众视为耕战机器，这套法度适合原本的“戎狄之邦”，却与六国文明格格不入。
原创翻译：龙腾网 https://www.ltaaa.cn 转载请注明出处

For a civilized society, it must have the ideological value that the people acknowledged voluntarily. Especially in peacetime, besides food and clothing, the people also need the ideological construction.Therefore, the collapse of Qin State was so tragic. An ordinary peasant can overthrow it easily when they rose up in arms. Its collapse did not cause any nostalgia among the common people and literati.

文明社会需有民众自愿认同的价值观。和平年代除温饱外，更需思想建设。故秦亡时，一介农夫振臂即可倾覆王朝，而百姓士人无一怀念。

Thai Nguyen Gia
You can consider the whole Qin dynasty, and the first generation of Han dynasty, as one grand unification war, with Qin being first campaign, and Han being the other, each campaign last for decades.

可将秦朝与汉初视为一场统一战争的两个阶段：秦为第一阶段，汉为第二阶段，各持续数十年。

Because the whole thing is to break down seven countries to become one empire, and the whole thing is difficult beyond belief, so it require time more than anyone dare to think about. So the Qin falls is inevitable, really.

因“七国合一”的难度超乎想象，所需时间远超世人预估，故秦亡实属必然。

First, Qin dynasty defeat all 6 other countries. But since they didnt do (couldnt and wouldnt) the genocidal thing , there obviously left the remnant resistance from each country. This is inevitable.

秦虽灭六国，但未（也无力）实施种族清洗，各国残余势力必然存在。

The embers of resistance burnt quietly under the heavy suppression of Qin occupational army. Even with the whole unification policies to integrate 6 other countries into Qin, it still burn.

在秦军高压下，反抗火种始终未灭。即便推行书同文等政策，抵抗仍在持续。

So when the first Emperor die and the fight for the throne between Qin princes broke out, the resistance fire up all over China. it lead to a total revolt, with the last faction standing, united whole country, become Han Dynasty later on.

故始皇一死，诸子夺嫡，反抗之火瞬间燎原。最终胜出的势力重整河山，建立汉朝。

In that process, most of local resistance either die out, or integrated into Han Dynasty. So the opposition to this unification process die down.

在此过程中，地方抵抗势力或消亡或归顺，统一进程的阻力终被瓦解。

I repeat, the fall of Qin is absolutely inevitable in order to unite 7 countries into one China.

重申：要实现“七国归一”，秦朝之亡绝对不可避免。