How and why did Ming China isolate themselves in the late 15th century?

This was done so as to focus on the inward development of the country

Explanation:

The Ming Dynasty ruled China between the Yuan and Qing Dynasties from 1368 until 1644. During this period, the ruling Emperors of the Ming Dynasty   decided to isolate China from foreign influences so as to focus on the inward development of the country. The Chinese at that time already had enough technology and did not have need for resources from other countries.

when a country suffers, for example, a drought period, the market product is affected for a low offer, in this case, potatoes; the government has to tax to the households, which have to give more money for the potatoes which they consume, that situation make them consume substitute goods even through loans, it could increase the financial market movement and the inflationary phenomena, the business has to increase salaries in order to the employees could buy a more expensive food (potatoes) and in order to inflation tha business had to buy expensive supplies in the factor market, while the rest of the world have to gain more money to consume the same amount of potatoes.

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