I would say the simple ways. We say that there are only three types of systems. And our first job is to identify that problem. And that's the diagnosis and characterization. So simple problems but this causal relationships are well understood. Complicated is often ambiguous but not easily identified but you can see identify this. Then you have complex problems not easily identifiable only perceivable in retrospect. So a good example of this would be like flushing your toilet. You can go and buy a basically a toilet system from Home Depot for $100. It will work out very nicely. No problem. Bringing water to your home from Kauban like about 50 miles away and taking the water on the 16th floor if you room and you get out you get warm water, that's a complicated system. I need lots of pumps and pipes and then chlorination and heating and so on. Complex problem is the one then when we created this Kauvan Reservoir we have also eliminated four villages from Kaua because we wanted to create a large reservoir. A lot of people has lost their homes and they had to be bought out so was this the to do? Because you are basically removing human beings from four towns for 200 years because Boston has to grow. Boston needed more water