Imagine there is a place where the lake and the earth there are red in colour. Mainly because the soil there has a distinct red colour that gave the landscape a distinct reddish hue. This place became so popular and the government decided to develop it into a tourist attraction. They build houses that have a distinct red colour to it, and a ferry terminal to cater for boat rides. They named the place Red River Park. The ferry terminal, the red houses, the red hill, and the red river are all conditions to create a single entity called Red River Park. People who are familiar with this place would describe these distinct features when asked whether they have been there before. Now, if one day the government decides to revamp the place and make it even more commercialised, for example, by demolishing the red houses and build restaurants and pubs there, I am sure people would still recognise that place as Red River Park. The underlying conditions are still there. Mainly the red earthly colour of the terrain and lake. The same water that runs downstream to another village located hundreds of kilometres from the Red River Park would not have the same reddish hue to it. And if you were to ask the villagers there have they heard of the Red River Park and describe the colour of the water to them, you would most probably get a puzzled look. The same water that passes through natural filtration has become another colour. Obviously, we cannot say they are the same colour anymore. One is greenish, the other is reddish. But neither can we say that they are different either. Because it is the same water that flows continuously from the upstream to the downstream. What happened then? Causes and conditions at work. At a different location, the same object is subjected to a different set of conditions, thereby altering the characteristic of its original form.
Nothing is enduring enough to survive for infinitely long period without change and destruction. But we also cannot deny the existence of the Red River Park and our bodies too. They truly exist, but they exist for as long as the causes and conditions permit. We can see them as a process-self or impermanent-self. We are never a substance-self. There is no core essence in anything that can appear and operate on its own indefinitely without any cause and condition.