Tameshimono (試し者) as an Occupation — The Reality and Social Status of Test-Cutting Specialists Officially Recognized by the Edo Shogunate

As a means of measuring the performance of Japanese swords, a practice known as "test cutting" (tameshigiri) became institutionalized during the Edo period. The profession that specialized in this practice was known as a "tester" (tameshimono), and it was established as a specialized skilled occupation that determined the cutting ability of swords under the official approval of the shogunate. This article clarifies the actual circumstances and social positioning of this profession, which is little known today, through its relationship with the sword industry.

The Origins of Testers—Test Cutting Practices of the Sengoku Period

The practice of test cutting itself existed before the Edo period. It is said that swordsmiths had long possessed the habit of performing test cuts on bamboo, straw bundles, and wood to verify the cutting ability of completed swords. However, as the Edo period began and peaceful society continued, battlefield testing became difficult, and instead a formalized "test cutting system" became necessary.

The Edo shogunate established a system officially permitting test cutting using the bodies of executed criminals and appointed specialized craftsmen called "otameshigoyō" to carry out this work. This "otameshigoyō" was the prototype of the institutionalized tester profession.

The Yamada Asaemon Family and the Establishment of the Tester System

The family that held the most prominent status as testers during the Edo period was the Yamada Asaemon (yamada asaemon) family. From the first-generation Yamada Asaemon Sadatake onward, they inherited this profession through successive generations and received official recognition by the shogunate as "otameshigoyō." The duties of the Yamada family extended far beyond simple test cutting to include the following fields:

• Assistance with executions
• Evaluation of sword performance
• Editing of the "Wazamono Ranking" (wazamono bandzuke)

The Yamada family was treated as having a status comparable to hatamoto (low-ranking hereditary samurai without official position) and also provided instruction in swordsmanship, occupying a unique social position within samurai society. However, as their profession involved handling the bodies of the dead, they were conceptually linked to the notion of "defilement" (kegare) and thus occupied a socially delicate position.

Specific Procedures of Test Cutting

The institutionalized test cutting of the Edo period was carried out following strict procedures.

Test cutting used the bodies of executed criminals (bodies after beheading) at the shogunate's command. The bodies were typically used within several days of death, and depending on which part was cut, the posture, and the angle at which the sword was introduced, the following names were established for different test cutting methods:

• koshine (lower back bone)
• dō (torso)
• kesa (diagonal cut)
• yottsu (four-way cut)

The names of these test cutting methods later became established as words indicating the "cutting ability ranks" of swords.

After testing, the Yamada family issued a formal "test certificate" (tameshigaki). This document recorded the following items and functioned as a "certificate of authenticity" for the sword:

• The blade's signature
• The test date
• The type of test cutting method
• The result of success or failure

High-ranking test certificates became an important added value that increased the value of swords.

Connection with the Wazamono Ranking—How Testers Determined Sword Rankings

The "Wazamono Ranking" (wazamono bandzuke) regularly compiled by the Yamada Asaemon family was widely distributed in Edo society as a ranking of swordsmiths' cutting ability. Following the format of sumo rankings with categories such as ozeki, sekiwake, and komusubi, this ranking system classified swordsmiths and directly affected the actual market prices of swords.

Swordsmiths ranked in the upper positions of the ranking were classified into the following four categories, which functioned as a quality guarantee of their cutting ability:

1. wazamono
2. yoki wazamono
3. dai wazamono
4. saijō dai wazamono

In modern times, works by swordsmiths that received the evaluation of "dai wazamono" continue to receive high valuation, demonstrating that the influence of this Edo-period tester system continues to the present day.

The Technique of Testers—Cutting Technique

Testers required not merely brute strength but highly developed sword technique. In order to fairly evaluate a blade's cutting ability, the angle of the cut, the speed, and the trajectory of the sword had to be consistent. If individual differences affected the results, fair performance evaluation would not be possible.

The Yamada family is said to have transmitted "specialized test-cutting sword technique" through successive generations. The training required to maintain a consistent posture, consistent speed, and consistent angle of blade entry is believed to have possessed its own unique system distinct from ordinary sword practice.

Furthermore, compensation for the condition of the body (time elapsed since death, physique, etc.) had been accumulated as technical empirical knowledge, and this compensation knowledge was also an important element in the technical evaluation of testers.

The Relationship Between Testers and Swordsmiths

The relationship between testers and swordsmiths, though it might appear adversarial at first glance, had a strongly cooperative character in practice. For swordsmiths, having their blade certified as "wazamono" or "dai wazamono" was the highest honor and became a powerful sales promotion material for customers.

As a result, many swordsmiths voluntarily requested test cutting, and not a few swordsmiths paid fees to the Yamada family to obtain test certificates. This "commissioned test cutting" performed a function close to modern third-party product certification.

On the other hand, when test cutting results were unexpectedly poor (when a blade failed to withstand the test), there was risk of damage to the swordsmith's reputation, making the decision to request a tester's evaluation a matter requiring careful consideration.

The End of the Tester System After the Meiji Era

The Edict of 1870 abolished the test-cutting system. Prior to the abolition of the test cutting (yōgiri) system by government proclamation in 1870, the tester system had been abolished through government legal reform. The use of human bodies for test cutting was promoted for elimination by the Meiji government as a "barbaric practice," and the Yamada family's position disappeared.

The disappearance of the tester profession created a void in methods of evaluating sword cutting ability. In modern times, test cutting using plant materials such as bamboo bundles and straw bundles (demonstrations in modern iaido and battōjutsu) is performed, but the institutionalized test cutting on human bodies has never been revived.

Conclusion—The Role of Testers in Sword Culture

The profession of tester functioned as a "third-party certification body" for objectively evaluating the cutting ability of swords in the Edo sword market. Through the compilation of the wazamono ranking, they graded swordsmiths, and notably, this evaluation continues to influence modern assessment. Testers were specialist craftsmen who systematized the functional value rather than the artistic value of swords, and should be evaluated as important figures who supported the practical aspects of sword culture.