When we started out, we were among the first. Beijing had no and Shanghai had very few large buildings. At that time, it was all about building, building, building - and then selling, selling, selling. We were working like a manufacturer. Soon, however, we realized that land was running out in Beijing and Shanghai. So we started keeping our buildings, and managing and renting them out. We became landowners. That was the second act.

Investors don't like uncertainty. The market is telling us that they need certainty, they need to see where the economy is heading. If the government is committed to continue the Open Door policy, they will need to come up with concrete policies and execution steps to increase confidence.

It's a good thing that it is getting simpler to register a company in China, it is good that the exchange rate of our currency is getting more flexible and that it's getting easier for Chinese businesspeople to travel. All of this opens up our economy.

Our tenants now are companies like Uber, the taxi service, Meituan.com, China's version of Groupon - and a large number of startups. These companies operate in a modern way, just like their customers: They go on the Internet, look for an offer and take it.

I'm afraid what we are building today will not have the same impact and sustainability of the architecture of a 100, 500 or 1,000 years ago. The buildings of those days were miracles. We don't perform such miracles today. So we should be a little more modest. For my part, I'll be glad to show one of my buildings one day to my grandchildren and say: I'm proud of that.

Because people along the route had realized that there was demand and quickly organized supply. That's so Chinese. In a well-organized country like Germany, such a problem may not have arisen in the first place, but in China people immediately recognized an opportunity.

We have become so quick and effective in building things today. It would be easy to build another Pyramid of Giza or another Great Wall. But these buildings haven't withstood the test of time because of their building quality. They stand tall because they have a symbolic value, they represent a culture.