Challenges in which one of the parties had a physical disability which could in some way impact their participation was handled in various different ways. Dueling was practiced in many countries, over the span of several hundred years, so I'll be flitting across a few different examples to paint a rough picture, but I'd stress there is no single, unified answer here, and that certain examples of disability could at some times be fairly well accommodated, while in others almost entirely ignored.

To start at the most basic, while hardly driven by this specific need, the turn from sword to pistol as the common dueling weapon certainly opened up opportunity here by removing a good deal of the physical barriers that a sword fight - and its accompanying movement - presented and replaced it with the more static nature of a gun fight. While it was often (but not always) convention that the challenged party could choose the weapon, it was also convention that sword could be rejected for pistol if the other party was not versed in swordsmanship. This applied broadly beyond disability, although nods were made here to men who were missing limbs as a specific reason to avoid the sword and the benefit it provided there is plain enough, but additionally, as we'll see, this would be one of the very few ways the challenger would find themselves accommodated by the conventions of the duel if they were in some way disabled.

But that is very general, and I'd like to dive into a few examples of how these issues more specifically manifested themselves. Perhaps the wildest is if we go back to the early origins of the duel in Renaissance Italy. As you note, there was great emphasis on equality within the discourse on dueling - it being a contest between two social equals - and a number of early writers on the topic of dueling stressed that physical equality mattered as well, but they also stressed that it only mattered with the challenged party. If someone issued a challenge to a duel, they were putting themselves forward 'as is', so to speak. Any disability they possessed they full well knew when challenging, and they essentially had to accept that and adapt best that they could.

But again, for the challenged party, equality was paramount and some treatises argued that this needed to be accommodated best that could be done. In the case of extreme disability that prevented combat at all, the use of a substitute would be considered appropriate - a brother, a son, or a trusted friend - which was something that under normal circumstances would be seen as cowardly. It was acceptable in cases of infirmity, as well as illness, but these required statements of honor, or examination by a doctor to agree they were unable to fight.

For cases where disability didn't prevent combat, it was considered proper by many dueling authorities to find ways to handicap the non-disabled challenger to put them both on as equal grounds as possible. Basic examples that were followed here would include patching over the eye if the challenged party was missing one. More serious writers would go so far as to contend that merely covering was not sufficient, and the challenger ought to have their own eye put out, the argument being that although covered, knowing he nevertheless had a second eye created a disadvantage for the other man since while he could afford to lose one, his opponent couldn't!

Just how extensively this was practiced in the late 15th to early 16th century is unclear, but it is generally unmentioned by the mid-16th century, and to be sure other writers on honor and dueling considered it to be an absurd suggestion from the start. Other ways to bring about physical quality which can be found in texts from the period include weakening the challenger by forcing them to fast prior to the fight, or by performing a bloodletting, but this too started to die out by the early 1500s, leaving only the temporary handicappings to be followed.

Similar limitations were also enforced in the choice of armaments. While unarmored fights with the sword would come to be standardized by the end of the 16th century, duels in the earliest periods would often involve armor, and extensive selections of arms, and it was understood that specific choices which created an unfair advantage could be rejected. The continued focus on the eyes again manifests itself here, a common example being the choice of helmet, and the right to reject one which might interfere with the sight of a one-eyed duelist to their disadvantage.

It ought to be noted that the desire for equality only went so far though. For instance, a one-armed duelist did not create a situation where the writers were claiming the other duelist needed to cut off their arm, and it wasn't even the case that the second arm would be immobilized. However, if the duelist had lost their right (dominant) arm their opponent might be forced to accommodate them by fighting with their left as well. Although hardly the only reason, it was certainly one of the factors that led to men of honor training to fight with either hand to ensure skill under such circumstances.

To be sure, just as some writers opposed the extreme measures above, others opposed any attempt. This tied into other debates about the relationship of the duel and war. For those who believed the duel ought to be viewed as similar to war, they argued that equality could not be expected on the battlefield, and thus combatants should not expect it on the dueling field either. Although supportive of allowing substitutes in the case of a (legitimately) complete inability to partake in combat, if capable of fighting, both parties needed to fight as they were, just as in a real combat.

As I said though, the expectations varied greatly, and it is hard to find a time and place for where there was more arguing about the nature of honor and the philosophy of the duel than what we see above in Early Modern Italy. Some discussion and articulation did exist, to be sure, even if we lack the sheer volume of writing produced by the Italian 'doctors of honor'. The next best example would possibly be 19th century Germany. Insults were 'ranked', minor insults being more appropriate to duel with swords, and more serious insults to be generally dealt with via pistol, and it was understood that for a lower-level insult, a missing limb would be appropriate reason to decline a challenge to fight with swords, and likewise a missing eye could avoid a less-than-ultimate challenge with pistols, but at a third-level insult, (i.e. the most serious, and nearly always done with pistols) avoidance for such reasons was harder.

All in all though, there just isn't the same amount of literature or concern found in writings of 19th c. Germany, let alone, say, 18th century Ireland. In some part, we can ascribe this to the rise of the pistol, which while hardly eliminating ways in which persons with disabilities could be disadvantaged, did eliminate some inequalities in comparison to the sword, but hardly all, especially disabilities which might relate to sight, or grip. Movement would, for the most part, not be an issue though, as while the common image of the duel might have the duelists back to back and walking away from each other, this was exceedingly rare, and a duel with marks carefully measured out, and the duelists placed there by their seconds simply to await the signal, were far more common. While various types involving movement existed, a set mark was fairly common and could be easily expected in the case of one duelists trouble or inability to move about. With pistol duels, it is interesting perhaps that one of the major concerns being target area, the accommodations sometimes would go in the reverse, the thinking being that a person missing a limb had an advantage of one less thing to be hit.

The best known story to illustrate this is from a possibly apocryphal duel that occurred in Georgia maybe in 1802, were Judge John M. Dooly was set to duel Judge Charles Tait. The latter had a wooden leg, and Dooly, arguing that it would be unfair for him to risk his second leg when Tait had only one to hazard, proposed to have a short stump from a gum tree in which he could place one leg to protect it. Interestingly, the humor of the proposal diffused the tension of the encounter and allowed an accommodation to be reached which avoided the duel itself!

A second - and better attested to - account of a duel in Louisiana between Captain Foster and Mr. Molineaux proceeded similarly, although it was Capt. Foster, who possessed a wooden leg, that insisted Mr. Molineaux be provided with a wooden board to protect his leg, which Mr. Molineaux attempted to decline until giving into Foster's insistence. He made the right choice, as we are told that both duelists ended up shattering wood with their bullets.

Of course, again, these are both accommodations not made for the duelist with disabilities, but rather his non-disabled opponent, but I do think they illustrate how at least in these cases the type of disability - a missing leg - that would have been a major impediment to a duel a century or two earlier with a sword, was something remarked on only in the way it created a disadvantage for the other duelist.

The only accommodation that comes to mind to eye-sight, and accommodation is kind of an odd thing to call it given the result. Typical duels were conducted ranging from 10 to 12 paces. Sometimes considerably further, as in France where 30 paces was typical, but rarely much closer. While a closer distance often was indicative of some extreme animosity between the parties, at least a few duels in the record show this done as an accommodation to the near-sightedness of one of the participants.

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