436 MILITARY REFORM
[Our country] is divided into yangban and commoners [sang'in], and there is
difference between the noble and base. The so-called private slaves [sach on]
are multiplying in numbers by the day and month and are counted in the thou-
sands and ten thousands. Not one of them has military service while the men
of good status [yangmin] are burdened with such heavy taxes that they cannot
make ends meet and have gradually been driven into running away from their
homes. Everywhere people have ended up [as slaves] of private families, [the
heads of] which are treated like the dukes and marquises of ancient China while
the state has no people left of its own. This was the reason that worthy states-
men of the past wanted to institute laws to limit the amount of land and the
number of slaves [that private families could own]. Their ideas were really far-
reaching. I13Yu pointed out that earlier in Korean history, when slavery was less of a prob-
lem, smaller states than Choson had been able to mobilize larger armies. Back
in the Three Kingdoms period, when Koguryo was left alone in the northwest
to face the armies of the Chinese Sui and Tang dynasties (ca. 6 I 2-68), she was
able to muster several tens of thousands of soldiers in her walled fortresses and
towns and raise an army of 150,000 troops to relieve the town of Ansi. In the
Koryo period when the famous generals Yun Kwan and Kang Kamch'an fought
off the Jurchen and Khitan, both of them had armies of 200,000 men behind
them. In the Choson period, by contrast, the country had never been able to muster
a force larger than about 10,000 men, "a situation [that was the product] of accu-
mulated decline and dire weakness that did not come about overnight." I 14
Back in the 1590s, when Korea was facing the crisis of invading Japanese
armies, it made no sense at all to say that "old customs cannot be changed and
the feelings of the people [against slave participation in the army] cannot be
violated." This is why King Sonjo not only insisted that people learn how to
shoot muskets, he also enrolled "those private slaves who lived in different res-
idences from their masters in the ranks [with them] and named them sog'ogun."I 15
It was even less possible to ignore slaves in seventeenth-century Choson than
before because now slaves were 80 to 90 percent of the total population. "If you
abandoned the slaves [from one's calculation of military service], there would
be no people in the country left."1 16 Even though this statement was punctuated
with exaggerations (there were more than 10,000 men in the army, and the slave
population was closer to 30 than 80 percent), the point here is that Yu was
unabashed in his willingness to sacrifice the welfare of the slaves to alleviate
the burden on commoners.
Even though Yu was advocating the necessity to enroll slaves for military ser-
vice, he was not willing to tolerate the admixture of slaves and commoners in
the sog'o units, as they had been since the Imjin War. Pandering, no doubt, to
the sensitivities of social conservatives, he explicitly stated that the sog'ogun of
his system would consist exclusively of official and private slaves. I I7 He
instructed that caution be exercised against allowing public or private slaves into