After Li Tang got the country, the first thing he did was to announce the reduction of the agricultural tax of the common people. This is why the people in various parts of the country who are in turmoil have gradually settled down. But a new problem arose, Li Tang lowered the agricultural tax, and the imperial court could no longer support the army and officials. The army could not be easily disbanded, and the officials could not suspend the payment for a long time, forcing the emperor to come up with a way to deal with it, otherwise the newly formed dynasty would be replaced by other forces. Tang Taizong Li Shimin came up with a way to deal with it, which was to encourage everyone to do business. Although the status of a businessman cannot be changed all at once, appropriate encouragement is given. Soon after, the effect came out, and due to the circulation of merchants, the common people everywhere exchanged what they had and what they needed. Not only did it reduce the people's grievances, but it also improved everyone's lives, and the surplus materials brought by the war were quietly sold to foreigners at high prices. The imperial court also made a lot of money because of the merchants' taxes, which was enriched into the treasury and alleviated the expenditure problem of the imperial court.

Li Shimin and his descendants discovered the benefits of doing business, and at the same time saw the benefits of doing business. So while encouraging the people of the country to do business, they also reformulated the tax for merchants. As a result, there is a commercial tax that is very different from the agricultural tax. The rulers of the Tang Dynasty did not blindly designate the commercial tax, but through many inquiries and solicited the opinions of the merchants, the commercial tax was formulated.

After actual inquiries and consultations with businessmen, there were also some officials who did some business privately, and carefully recorded and settled accounts through the master of accounting in the household department. A more reasonable way of business operation expenses has emerged, generally a principal, plus the expenses of businessmen and associates, if there is no big risk, the province can earn three to forty percent of the profit. If you go out of the province, the profit is about five to seventy percent. If you sell goods from the South to the North, or if you transport the products of the North to the South, the profit is between two or three times as high, or even higher. If you ship goods from your home country abroad, you can make eight to ten times the profit. Excluding general risk and manual labor, a businessman can earn three to eight times the profit in a year. However, there are safety issues on the road, as well as the impact of goods deterioration or price fluctuations.

Li Shimin personally summoned several influential businessmen and asked for their opinions, and only then did he know what the businessmen were most worried about. The first is the issue of safety on the road. Second, there is the issue of supply. Third, there is the issue of risks brought about by price fluctuations. Fourth, there is the issue of the attitude of the imperial court. Fifth, there is the issue of the legalization of their income by the local yamen. Li Shimin made a bold decision to send troops to garrison various places first, protecting and securing merchants and goods along the way. Second, the imperial court could protect the merchants' legitimate acquisition rights and help the merchants coordinate the peasants' acquisitions. Third, the imperial court will intervene in the problem of domestic price fluctuations. Ensure that the goods received by the merchant will not be lost due to the problem of price fluctuations. When necessary, the imperial court would buy the goods in the hands of the merchants to relieve the financial pressure on the merchants. Fourth, the imperial court can promise merchants that it will not easily change the general policy of encouraging everyone to do business. Ensuring the status of businessmen in terms of policy, and at the same time standing up for businessmen when they encounter unfair treatment abroad. Fifth, the income earned by a merchant from doing business should be registered and legally proven. The imperial court and local yamen would not only protect, but also encourage merchants to buy land and establish branches and branches throughout the country.

Li Shimin's attitude made the businessmen very happy, and at the same time, they also knew that Li Shimin would not pay in vain, so they made some plans. Li Shimin also felt that the time had come, so he expressed the idea of increasing the commercial tax. Businessmen also feel that it is appropriate to raise commercial taxes, but they are worried that the taxes are too high. Some people are worried that the money they earned by working hard will end up in the imperial court.

Li Shimin knew that businessmen had concerns, so he came up with three ways to collect commercial taxes. The first is to settle the tax ratio according to the merchant's own accounting. In order to do business, a merchant needs to provide the name of the goods and the quantity of the goods, and calculate the cost according to the market price. Then, when selling, report the quantity and price sold by the local yamen. Based on the difference between buying and selling, the merchant's profit is determined this time. The yamen set the tax based on this profit. Second, the imperial court is one-size-fits-all. According to the four transaction methods of the province, outside the province, north and south, domestic and foreign, the tax standard is formulated. It is the lowest in the province, followed by the outside of the province, again in the north and south, and the highest at home and abroad. Regardless of how much the merchant made and whether he lost money or not, the imperial court collected the merchant's taxes according to the number of times. The third is the total calculation system, that is, according to the amount of the merchant's principal, no matter what kind of business the merchant does, the annual tax of the merchant is formulated. Even if a businessman does not go out for a year, he will be taxed, and even if a businessman makes a thousand times more money in a year. In the following year, a new tax amount is set according to the merchant's property.

The merchants calculated that the first type of tax was most suitable for merchants, but this right to set taxes was in the hands of the yamen in various places, and everyone was worried that the yamen people would do tricks intentionally or unintentionally. Besides, in this way, the businessman will have to look at the face of the yamen in everything, and there will be more "filial piety" in private, and it is better to hand over the money to the court openly. The second tax method is a bit overbearing, but it is easier to manage, and businessmen do not have to worry about extortion or difficulties from the yamen in various places. But in this way, businessmen do not dare to do business easily, because every time they report, they need to count this tax and add it to the cost. The third type of tax is more cost-effective, but it is also the most risky. If the business is going well and the business is very healthy, this is definitely the best way to settle the bill. But if the merchant is sick or has problems at home, the tax will become a big burden. In particular, after the businessmen thought of a key question, everyone felt that this solution was not suitable for everyone. The merchants thought of the need for the imperial court to calculate the merchants' property every year. This is tantamount to exposing the businessman's family background, which will attract the attention of many people. The people of the imperial court will pay attention, the people of the yamen everywhere will pay attention, the peers will pay attention, and the common people will be red-eyed. According to the principle of "wealth is not exposed", it is impossible for a businessman to expose his wealth to others.

The businessmen decided to settle according to the second tax method mentioned by Li Shimin, but there was a relatively big controversy over the proportion of taxes. Of course, the merchants wanted as little tax as possible, even equal to the agricultural tax. But the imperial court would not agree, because the profits of the merchants were much higher than that of farming. If the agricultural tax is "1 out of 20" or lower, the tax of the merchants is too low. The imperial court is simply escorting the merchants, and soon the merchants will have more money than the imperial court, which is not allowed by any imperial court.

Li Shimin was tougher this time and said a standard. If the merchants were willing to accept it, they could do business normally with the permission of the imperial court. If you don't agree, the court won't blame everyone. You can go back to farming, you can go abroad, but you are no longer allowed to do business at home. It is equivalent to forcing everyone to accept Li Shimin's decision, this is the benefit of power, and there is no need to worry about businessmen coaxing. It's a big deal to change a group of businessmen to do business, and there is really no one to do business on their own.

Under Li Shimin's strong coercion, the merchants had to sign a so-called voluntary agreement. Consciously and voluntarily cooperate with the imperial court, and pay taxes to the imperial court on time and in accordance with the amount. Ensure that the quantity and goods reported by yourself every time are facts, and never do false declarations. As for the proportion of taxes, it should be handled in accordance with Li Shimin's decision. The proportion of each tax in the province is 10% of the principal; Out of the province is one and a half or two and a half of the principal, and the tax ratio is determined by the local yamen according to the distance of the road; In the north-south direction, the tax ratio is 50% each time according to the one-way calculation. If you don't bring the goods when you go back, you don't need to calculate the tax; If you go abroad to do business, the tax is calculated according to the principal amount of each one-way trip. Merchants are allowed to make up the payment within the prescribed period after returning afterwards. In particular, penalties for false reporting and tax evasion are specified. If you buy more and report less, the excess goods and income will be punished by a fine of ten times the original price. If a merchant comes with goods and returns without goods, but secretly brings them, all goods will be confiscated and the merchant will not be allowed to do business for five years as a punishment. If the merchant did not report to the yamen and privately formed a team to do business, the yamen had the right to confiscate all goods and money, and at the same time, the merchant family would be disqualified from doing business, and the merchant and his associates would be confiscated at the same time.

This decision was very shocking to the merchants, especially those who were engaged in illegal business in private. But Li Shimin is the boss, and he has already formulated the rules, and everyone has to abide by them, otherwise the consequences will be very serious. Although the businessmen have a little money in their hands, their status is very low, and their families have no powerful backers. They can usually scare the common people, but in the face of a power structure like the imperial court, they can be said to have no ability to resist at all. Fortunately, Li Shimin gave them some space to live and did not force them to the desperate. According to Li Shimin's decision, as long as the businessmen do business in peace, they can not only survive, but also make a fortune. They had no choice but to agree, in fact, they couldn't do it if they didn't agree, Li Shimin had already arranged soldiers outside the door, if the merchants didn't agree to make a coax, Li Shimin would go on a killing spree.