Erizeni (also called erisen or sensen) indicates the act of not accepting low-quality coins (called bitasen coins or akusen coins) in payments, carried out in the latter half of the medieval period in Japan.
In Japan, commodity economy progressed from around the latter half of the Kamakura period, and coins became circulated widely. However, coins mainly made and used in China were generally utilized in Japan as well. These Chinese coins were brought to Japan through trade with China (Northern Sung Dynasty or Yuan). However, these coins included lots of those that were made privately in China or south-eastern Asia, and in Japan as well, counterfeiters who minted imitations of these coins appeared. These imitation coins were called shichusen coins (literally, the coins made privately). The quality of many of these shichusen coins was quite low: For examples, in some of them, a portion was lost, no hole was provided, or the characters on them were too worn to read them. Therefore, shichusen coins were likely not welcome, for example, not accepted as formal coins in payments in the commodity economy. The following are considered as the reasons why such a situation was generated: One is that the literacy rate of the people at that time was low, and another is that, being made privately, they were made irresponsibly. Therefore, these low-quality coins were called bitasen coins or akusen coins and were valued less than ordinary coins: For example, it was determined at the time that four bitasen coins constituted one mon ("mon" is a monetary unit at that time).
Entering the Muromachi period, Eiraku-tsuho coins, which the Ming Dynasty minted for payments in trade with Japan, became used widely in Japan. However, coins minted privately in Konan (Jiāngnán) of Ming and those minted privately in Japan became gradually mixed with the Eiraku-tsuho coins. Many of these privately minted coins were low-quality bitasen coins (whose surfaces were worn away). These bitasen coins were evaluated less than ordinary ones in payments, and it sometimes happened that these coins were not accepted. Other low-quality coins, such as those minted during the war era of Southern Sung Dynasty and coins in Ming as well, were handled in the same way. Such an act is called an erizeni act. Erizeni acts often caused trouble, sometimes leading to homicide.
Therefore, entering the 16th century, the Muromachi bakufu, shugo daimyo (Japanese territorial lord as provincial constable) and daimyo (Japanese territorial lord) during the Sengoku period restricted the erizeni act or issued erizenirei (a ban on the erizeni act) to achieve smooth circulation of the currencies. This is because those persons who controlled the foreign trade and possessed lots of coins brought from China were afraid that the values of these coins were downgraded. However, consciousness of avoiding bitasen coins and of carrying out the erizeni act was rooted strongly amongst the general public. Furthermore, Kaikin Policy (the policy to forbid private people to trade with foreign countries) and the establishment of a currency system based on silver and coins (excluding copper coins) by the Ming Dynasty reduced the necessity of minting copper coins, naturally decreasing the amount of copper coins that were brought into Japan as well.
Problems centered on the erizeni act were also generated partially because no strong centralized government existed in Japan during the sixteenth century. Therefore, such problems had been gradually eliminated as the centralized government, such as the Oda government, the Toyotomi government, and the Edo bakufu, were born. However, carrying out the erizeni act had also become customary among the general public for a long period of time. Therefore, the problems concerned with the erizeni act did not dissolve for a long time until, in the Edo period, the Edo bakufu issued Kanei Tsuho coins with stable quality and severely prohibited minting coins privately. Nobunaga ODA initially aimed at prohibiting the erizeni act by imposing a severe punishment for such action. However, although issuing high-quality copper coins could lead to a fundamental solution of the problem, he could not do it because he didn't have a large mine in his territory. As a result, people avoided using copper coins, causing the circulation of money in the Kinai region (the five capital provinces surrounding the ancient capitals of Nara and Kyoto) decline temporarily. Later, Nobunaga set an exchange rate between low-quality coins and high-quality coins to prevent the circulation of money from becoming stagnant. It is also said that, with such an economic situation as a background, the system of Kokudaka (assessed yield; tax system based upon rice, measured by reference to the rated annual yield of the domain) was introduced by the succeeding Toyotomi and Edo bakufu governments.
For some time after Kocho-Junisen (copper coins of twelve different types minted in Japan) was abolished, fuka, or bleached clothes and rice, were used in place of coins. However, as trade with Sung became prosperous, lots of coins minted in Sung were gradually brought into Japan. The amount was so huge that Sung prohibited trade with Japan (starting in 1171). However, entering the era of Southern Sung Dynasty, which was oppressed by Kittan (Khitan/Khitai), Chin Dynasty and Yuan Dynasty, the Southern Sung Dynasty issued lots of low-quality coins under a state of war, causing rampant inflation, causing the downgraded values of the coins, and resulted in forcing more and more coins to be brought into Japan.
These coins from the Southern Sung Dynasty and low-quality coins from the Ming Dynasty were called 'Imazeni' (Kinsen, Nankinsen), 'Kobu, Eiraku,' or 'Imazeni, Seisen,' and merchants and others who were afraid that inflation could be generated differentiated good-quality coins from bad-quality ones and came to despise the latter coins. There is even a theory that the great Buddha statute in Kamakura was made using the metal obtained by melting surpluses of these imazeni coins. Because each Chinese coin was of small-value, these coins were valued in a unit of 100 thousand kans (a unit of bundling coins; 1000 coins/kan) (or 100 million coins) in some instances, and most of them were circulated as kansen coins or in their original, bundled, state. Therefore, to evaluate the quality of these coins, there were no other means except using external sizes and their thickness, cause bitasen coins to mix more easily and consequently downgrading their real values further.
In recent years, the following theory has been proposed as well: Wide use of silver in Ming degraded the credibility of coins in Ming, affecting, in some way, situations in Japan at that time. Silver was the currency of Mongolia, and in the Mongol period, coins of the Southern Sung Dynasty were already despised, compared with the currencies of the Chin Dynasty that had an external appearance of high-quality coins. In the Northern Sung Dynasty era before that, bills called koshi were issued, causing both copper coins and paper money to be used in the domestic economy of the dynasty. In the later Ming and Yuan periods, paper money became used increasingly more than copper coins. In addition, Japan bought lots of money that exceeded the amount of money issued, generating a situation whereby the amount of money available locally became insufficient. This situation made the money value fluctuate significantly, accelerating economic turmoil, and causing Kaikin Policy to be employed by Ming. In Ming, as the currency system based upon using both silver and paper money was established, the necessity of minting copper coins became lost.
Feature of bitasen coins
For the bitasen coins that were made based upon the reasons described above, some tricks were used to make these coins mainly for the purpose of being mixed with kansen coins. Because only the edges were visible, no consideration was given to many of their facets. It did not matter whether the characters on the facets were worn out or not.
The coins modified included 'surisen coins' and 'uchihirame coins.'
To mix these with kansen coins, the surisen coins were generated by making larger coins diameters smaller by grinding them down, and the uchihirame coins by making smaller coins larger by smashing them. In some cases, even shimonsen (literally, four mon coin - a unit of money) coins were ground smaller. This fact indicates that no credibility was given to such facets, even if these facets were those belonging to genuine Chinese coins.
It is difficult to appraise Chinese coins based upon existing ones, because, due to their low quality, they had been worn out or rusted. The situation is the same for coins made during the inflationary period of Ming, in addition to those in the war state, a huge number were issued and called 'Kinsen' (京銭) because they were concentrated in Nanjing, the capital of Ming Dynasty (南京) during its early period. Compared with high-quality coins issued during the era of the Northern Sung Dynasty, such as Kaigen-tsuho during the Tang Dynasty, they were as small as the present five-yen coin, with some of them as thin as an eggshell, and were made unevenly. Therefore, they were likely to 'become broken' (become broken coins). To have more accurate knowledge about bitasen coins, it is necessary to know the facts about currencies in China and other nations concerned, in addition to having knowledge about false coins and modified coins.
Proposed by Gresham, a financier in England in the sixteenth century, this theory is known from the expression; 'low-quality coins expel high-quality coins.'
This indicates the following concept: When two coins have the same face value, but are made at different costs are circulated at the same time, people collect coins with a higher value (high-quality coins) and keep them, not using them, or melt them to mint many lower-quality coins, and therefore, high-quality coins disappear from the market and inflation ensues. Once such a situation occurs, it is not a good policy to continue issuing high-quality coins. Therefore, the circulation of low-quality coins must be restricted to have high-quality coins used more widely.
Coins in dead storage
In Japan and China, a pot containing lots of old coins is sometimes unearthed. According to a theory, these coins were stored underground to ward off evil spirits, as a charm or for avoiding the disturbance of war, but according to another theory, they were stored to prevent them from being exchanged with low-quality coins. In Japan, the remaining rate of coins issued during Northern Sung Dynasty and that of older ones issued during Tang Dynasty are extremely high, and in China, it is said that Kanei coins remain conspicuously in dead storage.