讨论：为何骑兵这么有用？

Dagonus
In theory, it is easy to counter cavalry by holding formation. Horses do not want to run into you and often will resist charging straight into someone.This is especially useful if you have spears, pikes, or fixed bayonets. If you give the horse space to run past you, it will just alter course slightly into that gap. Unfortunately for you, it will also bump into you, knock you over and the next horse will trample you. In one of my military history class I had years ago in my undergrad, a student asked "so why don't people just hold formation?" The professor climbed on top of the table the student was sitting at and shouts "You're the front line! I'm this much taller than you! I weigh half a ton more than you and I'm charging at you at a run! If you hold formation, the horse will probably fall on you. Do you think you're holding formation?" "Maybe?" "Only if you are really, really disciplined and not overly stressed from the earlier actions." In short, a cavalry charge is terrifying, especially for undisciplined or green infantry.

理论上，保持住队形是很容易对抗骑兵的。马匹不想撞到你，通常不会向人冲撞，如果你有长矛、长枪或固定刺刀的时候会更有效。如果你旁边的空间足够马匹绕过去，它就会稍微改变路线进入这个间隙。然而不幸的是，它还是会碰到你，把你撞倒，然后下一匹马会把你踩死。几年前，在我本科的一堂军事历史课上，一个学生问“既然如此，那人们为什么不保持住队型？” 教授爬到学生坐的桌子上，大声说“你是前线！我比你高这么多！ 我比你重半吨，而且我正在向你冲锋！如果你保持队形，马很可能会撞在你身上。你确认你要保持队型？”“可能…吧？” “除非你真的真的很有纪律，并且没有因为之前的行动而过于害怕才有可能。” 简言之，骑兵冲锋很可怕，特别是对于那些没有纪律的军队或新兵。

Not_A_Sholva
It's worth noting that the further back you go in time, the less the difference in size between a horse and a man is though. Sure, people were smaller too, but horses have been deliberately bred to be bigger for thousands of years. Especially if you go back some 5000 years, a rider would have to think about keeping their feet off the ground.

值得注意的是，时间越早，马匹和人的个子差距越小，当然，人的个子也更小，但马匹一直被有意的往大个子的方向培养。特别是在5000年前，骑手必须考虑要把脚提起来才能不接触地面。

ppitm
Virtually all medi war horses would be classed as ponies today. 14 hands and under.
There is only a single archaeological find of a 15 hand horse in the medi period.

实际上，中世纪的所有战马都会被归类为如今的小型马。高度在14掌以一下。
只有一列中世纪考古发现的马匹是15掌。

MattSR30
I could be misremembering, but I thought their size (and the lack of saddles/stirrups) were the reason chariots were used in the ancient world. They were too small to ride, but they could pull a chariot.

不知道我有没有记错，但我认为它们的尺寸(以及没有马鞍和马镫) 是古代使用战车的原因。因为它们太小了，不能骑，但它们可以拉战车。

_Mechaloth_
You're not going to ride a regular horse into battle; you're going to ride a war horse, meaning it was trained to counter some of its survival instincts (against its own, probably better, judgment). Also, horse bodies are a great way to break a spear line. Expensive, sure, but if sacrificing a horse against polearms means some capable men get inside enemy lines, you can be sure as hell they'll take that opportunity.
Also, carrying a shield may not be easy on a horse, but it's sure easier than walking with it through mud and gore. Same with weighty armors. Put a pointy stick in a guy's hand with the momentum of a charging horse and put that against a regular infantryman; advantage to the cavalry (nearly) every time.
A horse itself can be a weapon. A kick can be fatal, getting stepped on can be fatal. Even if someone just gets knocked over, they become an easy target.
I think you are severely underestimating the utility and "bravery" of horses. The latter is a result of training, even in huge animals like elephants.

骑去打仗的马不是普通的马，是战马，这意味着它被训练过对抗它的一些生存本能。此外，马匹的身体也是打破长矛阵的主要方式。当然，代价很高，但如果牺牲一匹马来对抗长柄武器意味着可以让强力部队突入到敌人的阵线里，那么可以肯定他们会抓住这个机会。
另外，在马上携带盾牌可能不那么容易，但肯定比带着盾牌在泥泞中行走容易。重甲也是这样。骑手拿着狼牙棒骑在马上冲锋对付普通步兵，结果几乎每次都对骑兵有利。
马匹本身就是武器。踢是致命的，被踩也是致命的。某人即使只是被撞倒，也很容易成为目标。我认为你严重低估了马匹的用途和“勇敢”。勇敢是训练的结果，即使是大象这样的大型动物也是要训练的。

whistleridge
Short answer: Physics.
Longer answer: Horses weigh ~1000lbs/500kg, can cover up to 35 miles/70 kilometers in a day, and can charge at 30mph/48kph over short distances. This gives you advantages of both speed and power. You couldn't catch light cavalry except with other light cavalry, and you couldn't withstand a charge from heavy cavalry except with other heavy cavalry or with a dense formation of spearmen. Spear formations aren't mobile though, so they have no ability to do anything more than stand there or move slowly in one direction.
Cavalry alone typically couldn't defeat well-led infantry (key word: well-led; they literally ride over poorly-led infantry), for precisely the reasons you describe. But it could flow around it, and wait out the infantry. You can only stand in a dense formation so long before you need to eat, sleep, and poop, and the cavalry could more or less lounge around at their leisure. This is what happened to the Romans at Carrhae. However, if the infantry was well-supported by other arms, then they couldn't be isolated and the cavalry couldn't do much but run in circles. This is what happened to Ney at Waterloo.
But the major advantage that cavalry conferred was off the battlefield. They could scout, screen advances, raid deep behind enemy lines, disrupt communications, and even serve as mounted infantry. If the other guy had cavalry and you didn't, it was roughly like fighting a war today where the other guy has air power and you don't - sure, you can still hold out, but it's a lot harder. Time and again in the late Empire and throughout the Middle Ages, powerful and well-led infantry units held a region only to be bypassed by cavalry that burned and raided everything behind them, until eventually the infantry was forced to move out. At which point it was defeated.
There's no one-size-fits-all solution. Infantry alone can't do it all, and cavalry alone can't do it. You need combined arms. That principle still dominates warfare today, which is why you see modern armies using such concepts as the deep battle, the extended battlefield, etc.

简单答案：物理。
长答案：马匹的重量约为1000磅或500千克，一天可以跑35英里或70公里，可以以每小时30英里或48公里的速度进行短距离冲锋。这为你提供了速度和动力的优势。你无法拦住轻骑兵，除非有其他轻骑兵拦截，你顶不住重骑兵的冲锋，除非有其他重骑兵或密集的长矛兵队形。但长矛队形无法移动，所以他们除了站在那里、或朝一个方向缓慢移动之外，什么也做不了。
单靠骑兵通常无法击败训练有素的步兵，原因和楼主说的一样（关键词：训练有素。骑兵真的可以碾死训练不足的步兵）。但骑兵可以绕着步兵跑，或者和步兵磨时间。你只能在密集的队形中长时间站着，而你需要吃饭、睡觉和大便，而骑兵们可以休息。这就是罗马人在卡莱战役中的遭遇。然而，如果步兵有其他部队的有力支持，那么他们就不会被孤立，骑兵也就没什么办法，只能绕圈转。这就是内伊元帅在滑铁卢中的遭遇。
但骑兵的主要优势是在战场之外。他们可以侦察、掩护前进，突袭敌人后方，扰乱通讯，甚至充当骑马步兵。如果对方有骑兵而你没有，这就像如今的战争中对方有空军而你没有。是的，你仍然可以坚持抵抗，但这要面临更多困难。在帝国晚期和整个中世纪，强大且训练有素的步兵占据着一个地区，却被骑兵一次又一次的绕过，袭击并烧毁了他们身后的一切，直到最后步兵被迫撤离。在某种程度上，步兵是被击败了。
没有单兵种包打天下的方案。步兵不能单独完成所有任务，骑兵也不能。你需要兵种组合。这个原则仍然主导着如今的战争，这就是你看到现代军队使用诸如纵深作战、扩展战场等概念的原因。

Hygro
In boxing we have weight classes because more weight beats being "a smaller target". Now your weight class is "horse".

在拳击中，我们有重量级别，因为更高的重量级能击败“更小的对手”。现在，你的重量级别是“马”。
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whistleridge
Yup.
Prime Ali and Tyson lose to a cow every time, and it's quick. Right of weight is inexorable.

是的。拳王阿里和泰森每次都输给一头牛，而且输得很快。重量级是无可阻挡的。

whistleridge
"Alright, Tyson is coming out, he's clearly here to fight, he ducks, he wea-...He's dead! The cow just...crushed him! It didn't even seem to feel his punches!"

“好的，泰森出来了，他显然是来战斗的，他躲开了，他…他死了！牛直接压死了他！它甚至没有感受到他的拳头！”

SRD1194
One thing I would add, in response to the "horses are easily startled" argument, the horses used for battlefield work were trained. Much like modern police dogs, war horses would have as many of their instinctive reactions trained out of them. Where a cart horse would run away, a war horse would charge, and rake the enemy with its hoves. Because of the advantages of a mobile fighting force, wealthy, sophisticated nations had breeding programs to make the best war horses. Think about modern thoroughbred horses and show dogs, but with the aim of breeding vicious, fearless, obedient animals. Then you have their rider train with them for months or years, desensitizing it to smoke, fire, noise, and anything else they might encounter on the battlefield.

我要补充一点，以回应“马匹很容易受到惊吓”的说法，用于战场的马是经过训练的。就像现代警犬一样，战马的本能反应也会被进行很多训练。在驮马会逃跑的情况里，战马会继续冲锋，用蹄子踢敌人。由于机动作战部队具有很大的优势，富裕、有经验的国家制定了繁殖计划，以培育最好的战马。想想现代的纯种马和表演犬，不过它们的目的是凶猛、无畏、顺从的动物。然后让骑手和它们一起训练几个月或几年，让它们对烟雾、火、噪音和战场上可能遇到的任何东西不敏感。

gnosis2737
Great response! I think people also underestimate how common it would have been for cavalry to dismount and fight using infantry tactics. Competent cavalry leaders would not order a charge if the situation didn't call for it. They would save their horses and fight on foot as needed.
Cavalry advantages:
Chasing, charging, ambushing, hit and run, scouting, general mobility.
Lastly, cavalry was different from infantry in that they were typically elite. OP compared cavalry units vs well-led infantry unit but historically infantry were the CHEAP warfare solution. Cavalry was best employed to terrorize undisciplined or under-equipped infantry formations.

不错的回复！我认为人们也低估了骑兵下马使用步兵战术作战的普遍性。如果情况不允许，合格的骑兵指挥官不会下令冲锋，他们会保住他们的马匹，并在必要时步行作战。
骑兵的优势：追逐、冲锋、伏击、打了就跑、侦查、机动性。
最后，骑兵不同于步兵，他们是典型的精英。楼主比较了骑兵部队和训练有素的步兵部队，但从历史上看，步兵是廉价的战争手段。骑兵最适合用来恐吓没有纪律或装备不足的步兵编队。

AnaphoricReference
From the 16th century onwards you increasingly see a formal distinction between cavalry and mounted infantry that just used a standard riding or pack horse for mobility but didn't fight on horseback at all. In earlier times that distinction existed in practice but was mainly a quality issue.
Obviously, given the huge mobility advantages of cavalry in a campaign and the costs of keeping horses, cavalry were ideally not just men on horses but the best men, carrying the best armour and weapons on horses sexted and trained for the purpose. Knights usually went on campaign with two or even three horses to make the most of their mobility and still have a fresh war horse for battle. And even then there are tactical circumstances which call for a dismount.

从16世纪开始，骑兵和骑马步兵之间的正式区别越来越明显，骑马步兵只是使用标准战马或驮马进行机动，但根本不骑马作战。在早期，这种区别在实践中是存在的，但主要是质量问题。
考虑到骑兵在战役中的巨大机动性优势和养马成本，在理想情况下，骑兵不仅是骑马的人，而且是最好的人，携带着最好的盔甲和武器，骑的马匹经过精心的挑选和训练。骑士出征时通常带两匹甚至三匹马，以充分发挥它们的机动性，并且仍然有另一匹体力充沛的战马用于战斗。即便这样，也仍然有需要下马作战的情况。

ActiveFrontEnd
I would imagine also that a calvary charge was pretty scary which would lead to routes for poorly trained infantry. And in an infantry route I assume calvary would be devastating. Are there accounts of leaders using this shock style or were the calvary too valuable to waste for risks like that?

我还可以想象，骑兵冲锋是非常可怕的，会让缺乏训练的步兵崩溃。在前进的过程中，骑兵的破坏性极大。有没有军队将领使用这种突击方式的记录，还是说骑兵的价值太高，不能冒这样的风险？
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jrhooo
I would imagine also that a calvary charge was pretty scary which would lead to routes for poorly trained infantry.
THIS is one of my most often referenced points, about warfare in general. People talk about "trained and experienced troops" but people tend to miss what the importance of that training and experience is. Whether its holding a battle line instead of running away from the scary charging horses, or charging into an ambush position, or moving up a beach instead of looking for cover, there are so many tactical situations where the correct thing to do that helps you survive is the exact opposite of the thing every human instinct would tell you to do.
Training is what A. Gives you the knowledge to know to do THIS not THAT, and B. gives you the discipline to force yourself to do THIS and override fear alarm in your head screaming THAT.

“我还可以想象，骑兵冲锋是非常可怕的，会让缺乏训练的步兵崩溃。”
关于战争，这是我最常提到的观点之一。人们常说“训练有素、经验丰富的部队”，但又往往忽视了训练和经验的重要性。无论是在面对冲锋的马匹时能坚守住战线而不逃跑，或是冲入伏击位置，或是聚集起来而不是分散寻找掩护，在许多情况下，能让你生存下来的正确做法往往与人类本能趋势下的做法相反。
训练的意义在于，1、让你知道做什么而不做什么。2、让你学会强迫自己做正确的选择，并克服你头脑中去做错误选择的恐惧。

CFA1979
Don’t forget the psychological impact of a 1000lbs animal charging at you are 50km/h with a guy on its back waving a sword/spear/etc. From my understanding, a cavalry charge was more about making the enemies try running away and breaking formation than actually smashing into said enemy like in the movies.

别忘了当一只1000磅的动物以50公里每小时的速度冲向你，而它的背上还有骑手在挥舞着刀枪时带来的心理冲击。据我理解，骑兵冲锋更多的是要让敌人逃跑从而打破队形，而不是像电影中那样真正地撞向敌人。

Thewhopper256
One thing I’ve always wondered about (and admittedly never looked into, so I’m rather ignorant on the subject) is what weapons cavalry used. I believe I recall that they largely used pikes and spears because being on a large horse you need reach. But I can’t imagine how you could land a solid spear shot on an enemy without losing your spear and then losing one of your great advantages. I imagine a sword would be rather difficult to be effective with due to the short reach, but certainly better than nothing. Would they use a pike first and then swap to a sword after they land a good hit and lose their pike? Or would they be able to use a pike for multiple hits?

有件事我一直想知道，骑兵使用什么武器？我从来没有研究过，所以我对这个问题相当无知。我记得他们主要使用长枪和长矛，因为骑在一匹大马上你需要打到人。但我无法想象怎么能在不失去矛的情况下用矛刺敌人？我想刀很难奏效，因为它的范围太小，但肯定比什么都没有要好。他们会先用长矛，然后在命中对方并失去长矛后换成刀？还是说他们能够用长矛进行多次攻击？

hurocrat
Lances and longswords early on, mainly (sabers in later times). Pikes were an infantry weapon designed to use against cavalry, basically a giant boar spear. Lances would be easier to withdraw after impact, though you'd still lose it fairly shortly which is why medi knights often carried more than one. But basically yes. The lance would be used for the initial charge to break an enemy's front line, then they'd use the sword for melee fighting after the breakthrough when lances just became too awkward for close quarters. A longsword or heavy saber was devastating from horseback because you could use gravity to add force to a blow, while the infantry's pikes just couldn't be used after the first clash. However, bear in mind that a cavalry charge's best weapon in momentum. If you're mixed up in a melee, you're doing it wrong. So ideally a cavalry charge would plow through, re-form, then do it all over again preferably after getting another lance.
Infantry responded with axes, bills, and halberds. Axes to bring horses down, bills and halberds to bring knights and cav troopers down off their horses.

早期主要用枪和长剑，后期用军刀。长矛是一种用于对抗骑兵的步兵武器，基本上就是一种巨大的野猪矛。长枪在命中后更容易收回，尽管仍然很快会失去它，这就是中世纪的骑士经常携带不止一把长枪的原因。但基本上，是的。长枪用于最初冲锋，以打破敌人的前排防线，在突破后，当长枪变得难以近距离使用时，他们会使用刀进行近战。一把长剑或重型军刀在马背上具有极大的杀伤性，因为你可以利用重力来增加打击的力量，而步兵的长矛在第一次冲击后就不能使用了。然而，请记住，骑兵冲锋最好的武器是冲击力。如果你卷入了混战，那么你就没做对。所以理想的情况是，骑兵应该冲锋而过，重新组队，最好是获得另一把长枪后来冲一次。
步兵用斧头、枪和戟来应对。斧头可以把马砍倒，枪和戟可以把骑士和骑兵从马上拉下来。

MansfromDaVinci
Horses are more easily fed, housed and trained than elephants and they don't go berserk and attack the nearest thing nearly as much.
Also missile cavalry like the Numidian cavalry was effective because you can't catch them with infantry or heavy cavalry, they can ride down your ranged foot soldiers if exposed and fight fairly equally with light cavalry. You almost always fight on their terms after taking their shots. The Numidians only had a few javelins. Parthians, armed with composite bows, were absolute terrors

马比大象更容易喂养、培育和训练。它们也不会想大象那么容易发狂然后攻击最近的东西。
另外，像努米底亚骑兵这样的投掷骑兵也很有效，因为你无法用步兵或重骑兵拦住他们，如果你的远程步兵暴露了，他们可以和轻骑兵一样进行践踏。你几乎总是按他们的节奏来战斗。努米底亚人只有几支标枪。帕提亚人配备了复合弓，相当恐怖。
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lobibobo
The Mongols also perfected firing bows from horseback and it was a huge advantage in battle

蒙古人还完善了骑射，这在战斗中是一个巨大的优势

Cogust
Cavalry is extremely lethal to fleeing/routing infantry as you can't outrun them and you can't fight them off as your formation is in shambles.
If well drilled infantry held their ground, then the Cavalry would break off the charge at the last second and reform to try again somewhere else, or perhaps that feint managed to shake up your formation enough so that it is disorganised or demoralised enough for the next charge to succeed?
Charging into a spear wall will get you and your horse killed, even if you manage to break the infantry, so that was not something done voluntarily.
Cavalry generally doesn't want a prolonged melee, most of their advantages disappears and most of their disadvantages come to play, they want to feint, hit a flank, attack disorganised troops and then reform for another charge. Their mobility gave they ample opportunity to do this over and over and infantry most often had more than a single threat to face which often made it hard to face the Cavalry with a solid spear wall.

骑兵对逃跑、溃散的步兵是非常致命的，因为你跑不过他们，由于阵型是混乱的，因此也打不过他们。
如果训练有素的步兵能够坚守阵型，那么骑兵会在最后一秒结束冲锋，在其它地方集结再试一次，或许这种佯攻足以撼动你的阵型，使组织混乱或士气低落，让下一次冲锋能够成功。
冲进长矛墙里，哪怕你设法击溃了步兵，也会让你和你的马被杀死，所以骑兵不会主动这么做。
骑兵一般不想进行长时间的混战，这会让他们的大多数优势消失，劣势暴露。他们想要佯攻，击敌侧翼，攻击混乱的部队，然后重组进行下一次冲锋。他们的机动性让他们有足够的机会一遍又一遍地这样做，步兵通常面临不止一个威胁，这使得他们很难用坚固的长矛阵面对骑兵。

AgoraiosBum
Because infantry was often so shitty. When you have poorly trained and armed green levies being asked to fight your battles, and they are facing a warrior caste that spends life in the saddle, often with superior arms and armament, on a 1000 lb horse, bearing down on you, the natural instinct is to break and run.
Now, a well trained pike or spearman can stop the charge by holding their ground. But an army doesn't always have well-trained, veteran pike or spearmen. And if just a few people break and flee, it creates gaps in the line.
Secondarily, even if you have well trained infantry, if they are engaged with other infantry and the cavalry use their mobility to go around the back, the well trained infantry will still break.
Then, cavalry does its most important thing - ride down, kill, and scatter enemy who have broken formation and keep them from forming back up.

因为步兵通常水平低劣。当你缺乏训练、装备不足的新兵要求参加战斗，而他们面对的是一生都骑在马鞍上、装备优良的武器和铠甲，骑在一匹1000磅重的马上、向你冲来的战士阶层时，他们的本能就是崩溃然后逃跑。
训练有素的长枪兵坚守住队形确实能够阻止骑兵的冲锋。但军队里并不总是有训练有素、经验丰富的长枪兵。如果有一些人崩溃逃跑，就会在防线中造成缺口。
其次，即使你有训练有素的步兵，如果他们与其敌方步兵交战，而骑兵利用机动性绕到后面，训练有素的步兵仍然会崩溃。
然后，骑兵会做最重要的事情——践踏、杀死、驱散阵型崩溃的敌人，并阻止他们重组队伍。

gamerdude69
Imagine you and 9 of your buddies standing shoulder to shoulder, each with a shield at the ready. 3 mounted horses are 100 yards away charging at you in full gallop. All 3 of them smash into you with 1,000 pounds of weight at 30 mph. 2 of you will be borderline dead. 2 will be seriously injured. Half of you will have gone flying. Your line is broken, you've just been ran over by a horse at full speed, and now you have the wonderful job of fighting a mounted knight while you're in sandals.

想象一下，你和你的9个伙伴肩并肩站在一起，每个人都准备好盾牌。3匹马在100码外全速向你冲来。它们以每小时30英里的速度、以1000磅的重量撞向你。你们中有两个人濒临死亡，两个重伤，一半被撞飞。你们的阵型崩溃了，你刚刚被一匹全速奔跑的马从身上踩过，在这样的情况下，你还如何与对面的骑士战斗呢。